Australia’s National 
Science Agency 
Water resource assessment for 
the Victoria catchment 

A report from the CSIRO Victoria River Water Resource 
Assessment for the National Water Grid 

Editors: Cuan Petheram, Seonaid Philip, Ian Watson, Caroline Bruce and Chris Chilcott 







ISBN 978-1-4863-2105-6 (print) 

ISBN 978-1-4863-2106-3 (online) 

Citation 

Petheram C, Philip S, Watson I, Bruce C and Chilcott C (eds) (2024) Water resource assessment for the Victoria catchment. A report from the CSIRO 
Victoria River Water Resource Assessment for the National Water Grid. CSIRO, Australia. 

Chapters should be cited in the format of the following example: Bruce C, Petheram C, Philip S and Watson I (2024) Chapter 1: Preamble. In: 
Petheram C, Philip S, Watson I, Bruce C and Chilcott C (eds) (2024) Water resource assessment for the Victoria catchment. A report from the CSIRO 
Victoria River Water Resource Assessment for the National Water Grid. CSIRO, Australia. 

Copyright 

© Commonwealth Scientific and Industrial Research Organisation 2024. To the extent permitted by law, all rights are reserved and no part of this 
publication covered by copyright may be reproduced or copied in any form or by any means except with the written permission of CSIRO. 

Important disclaimer 

CSIRO advises that the information contained in this publication comprises general statements based on scientific research. The reader is advised 
and needs to be aware that such information may be incomplete or unable to be used in any specific situation. No reliance or actions must 
therefore be made on that information without seeking prior expert professional, scientific and technical advice. To the extent permitted by law, 
CSIRO (including its employees and consultants) excludes all liability to any person for any consequences, including but not limited to all losses, 
damages, costs, expenses and any other compensation, arising directly or indirectly from using this publication (in part or in whole) and any 
information or material contained in it. 

CSIRO is committed to providing web accessible content wherever possible. If you are having difficulties with accessing this document, please 
contact Email CSIRO Enquiries
. 

CSIRO Victoria River Water Resource Assessment acknowledgements 

This report was funded through the National Water Grid’s Science Program, which sits within the Australian Government’s Department of Climate 
Change, Energy, the Environment and Water. 

Aspects of the Assessment have been undertaken in conjunction with the Northern Territory (NT) Government. 

The Assessment was guided by two committees: 

i. The Assessment’s Governance Committee: CRC for Northern Australia/James Cook University; CSIRO; National Water Grid (Department 
of Climate Change, Energy, the Environment and Water); Northern Land Council; NT Department of Environment, Parks and Water 
Security; NT Department of Industry, Tourism and Trade; Office of Northern Australia; Queensland Department of Agriculture and 
Fisheries; Queensland Department of Regional Development, Manufacturing and Water 
ii. The Assessment’s joint Roper and Victoria River catchments Steering Committee: Amateur Fishermen’s Association of the NT; Austrade; 
Centrefarm; CSIRO; National Water Grid (Department of Climate Change, Energy, the Environment and Water); Northern Land Council; 
NT Cattlemen’s Association; NT Department of Environment, Parks and Water Security; NT Department of Industry, Tourism and Trade; 
NT Farmers; NT Seafood Council; Office of Northern Australia; Parks Australia; Regional Development Australia; Roper Gulf Regional 
Council Shire; Watertrust 


Responsibility for the Assessment’s content lies with CSIRO. The Assessment’s committees did not have an opportunity to review the Assessment 
results or outputs prior to their release. 

This report was reviewed by Dr Brian Keating (Independent consultant). Individual chapters were reviewed by Dr Rebecca Doble, CSIRO (Chapter 2); 
Dr Chris Pavey, CSIRO (Chapter 3); Dr Heather Pasley, CSIRO (Chapter 4); Mr Chris Turnadge, CSIRO (Chapter 5); Dr Nikki Dumbrell, CSIRO (Chapter 
6); Dr Adam Liedloff, CSIRO (Chapter 7). The material in this report draws largely from the companion technical reports, which were themselves 
internally and externally reviewed. 

For further acknowledgements, see page xxv. 

Acknowledgement of Country 

CSIRO acknowledges the Traditional Owners of the lands, seas and waters of the area that we live and work on across Australia. We acknowledge 
their continuing connection to their culture and pay our respects to their Elders past and present. 

Photo 

The Victoria River is the longest singularly named river in the NT with permanent water. Photo: CSIRO – Nathan Dyer


7 Ecological, biosecurity, off-site, downstream and 
irrigation-induced salinity risks 

Danial Stratford, Linda Merrin, Simon Linke, Lynn Seo, Rocio Ponce Reyes, Rob Kenyon, 
Peter R Wilson, Justin Hughes, Heather McGinness, John Virtue, Katie Motson, Nathan Waltham 

Chapter 7 discusses a range of potential risks to be considered before establishing a greenfield 
agriculture or aquaculture development. These include ecological implications of altered flow 
regimes, biosecurity considerations, irrigation drainage and aquaculture discharge water, and 
irrigation-induced salinity. 

The key components and concepts of Chapter 7 are shown in Figure 7-1. 



Figure 7-1 Schematic diagram of the environmental components where key risks can manifest during and after the 
establishment of a greenfield irrigation or aquaculture development, with numbers in blue specifying sections in 
this report 

For more information on this figure please contact CSIRO on enquiries@csiro.au



7.1 Summary 

This chapter provides information on the potential ecological, biosecurity, off-site, and 
downstream impacts, as well as the irrigation-induced salinity risks to the catchment of the 
Victoria River from greenfield agriculture or aquaculture development. It is principally concerned 
with the potential impact from these developments on the broader environment, but also 
considers biosecurity risks to the enterprises themselves. 

The ecological impacts of vegetation clearing associated with irrigated agriculture are not explicitly 
examined in the Assessment as it is considered of secondary concern to potential impacts on 
water dependent ecological assets. This is because irrigated agriculture occupies a very small 
proportion of the landscape (typically less than 0.5%) but can result in a disproportionately high 
degree of regulation of river flow. Consequently, the Assessment placed greatest effort in 
understanding the potential ecological impacts of changes in streamflow on aquatic dependent 
ecosystems. 

7.1.1 Key findings 

Ecological implications of altered flow regimes 

The flow regime in northern Australia is highly variable with large seasonal and inter-year 
variability. The natural flow regime is important for supporting species, habitats and a range of 
ecosystem functions. Species life-histories are often intricately linked to specific flow conditions 
considering the magnitude, timing and frequency of flow events. The ecological assets considered 
in this report represent a range of flow dependencies and have different spatial patterns of 
occurrence across the catchment. For ecology: 

• High flows provide a range of important functions including providing connectivity for 
movement, increasing productivity and nutrient exchange, providing cues for spawning and 
migration, and wetting habitat and supporting vegetation growth and persistence. The 
magnitude, duration and timing of high flows is important in ecological systems. 
• Low flows are also an important component of the flow regime with many species adapted to 
these conditions. Persistent waterholes provide important refuge habitat from environmental 
conditions and the higher levels of predation that may occur in connected rivers. For many 
species refuge waterholes function as a source for recolonisation during the wet season. 
Persistence in low flows during dry periods can help support suitable habitat conditions 
including thermal and water quality for species in connected rivers and in supporting riparian 
vegetation and movement and provide a source of water within the broader landscape. 
• The timing of flow events is important in supporting life-cycle processes including breeding and 
migration cues for aquatic species. The timing of flood events and the associated increase in 
productivity supports function in the river channel and connected marine environments. 


Although irrigated agriculture may occupy only a small percentage of the landscape, relatively 
small areas of irrigation can use large quantities of water, and the resulting changes in the flow 
regime can have profound effects on flow-dependent flora and fauna and their habitats. Changes 
in river flow may extend considerable distances downstream and onto the floodplain, including 












into the marine environment and their impacts can be exacerbated by other changes, including 
changes to connectivity, water quality and invasive species. 
The magnitude and spatial extent of ecological impacts arising from water resource development 
are highly dependent on the type of development, location, extraction volume and mitigation 
measures implemented. Ecological impacts, inferred here by calculating change in ecological flow 
dependency for a range of freshwater-dependent ecological assets. 
For water harvesting, impacts accumulate downstream, so ecological assets found near the 
bottom of the catchment experienced the greatest mean catchment impact. The largest 
catchment mean changes in flow dependencies for assets was for salt flats, mangroves, floodplain 
wetlands and banana prawns, all with moderate mean change in flow dependencies across their 
respective nodes. The largest single-site flow change under water harvesting scenarios were 
major, for assets including for cryptic waders, threadfin, prawns and floodplain wetlands. 
Mitigation strategies that protect low flows and first flows of a wet season are successful in 
reducing impacts to ecological assets. These can be particularly effective if implemented for water 
harvesting developments. At equivalent volumes of water extraction, imposing an end-of-system 
(EOS) annual flow requirement, where water harvesting can only commence after a specified 
volume of water has flowed past the EOS and into the Joseph Bonaparte Gulf, is an effective 
mitigation measure for water harvesting. However, the early wet-season streamflow in the Baines 
River is only moderately correlated with the early wet-season streamflow in the Victoria River, 
hence assigning an EOS annual flow requirement for each river may result in better ecological 
outcomes than a single EOS annual flow requirement for the entire catchment. For EOS annual 
flow requirements greater than 200 GL, additional mitigation measures (e.g. increasing pump-start 
capacity or decreasing pump rate) have little additional modelled ecological benefit. 
A dry future climate has the potential to result in a larger mean change to ecological flow 
dependencies across the Victoria catchment than the largest physically plausible water resource 
development scenarios. However, the perturbations to flow arising from a combined drier future 
climate and water resource development result in greater impacts on ecology–flow dependency 
than either factor on their own. 
For instream dams, location matters, and there is potential for high risks of local impacts. 
Improved outcomes are associated with maintaining attributes of the natural flow regime with 
transparent flows (flows allowed to ‘pass through’ the dam for ecological purposes). Potential 
dams located in small headwater catchments may result in a major change in the ecological flow 
dependency immediately downstream of the dam. However, impacts reduce downstream with 
the accumulation of additional tributary flows, so when averaged over the entire catchment or 
measured at the EOS, the change in ecological flow dependency is minor. Providing transparent 
flows improves flow regimes for ecology by reducing the mean yield of potential dams. Mean 
outcomes for fish assets can be improved from minor to negligible, and for waterbirds from 
moderate to minor, at catchment scales for the scale of scenarios explored. 


Biosecurity considerations 

Biosecurity is the prevention and management of pests, weeds and diseases, both terrestrial and 
aquatic, to limit their economic, environmental, social and cultural impacts. Economic impacts 
include reduced crop yield and product quality, interference with farming operations, loss of 
market access, and costs of implementing control measures. Environmental impacts include loss of 
biodiversity and changes to ecosystem processes, such as fire regimes. Social and cultural impacts 
of pests, weeds and diseases include diminished value of areas for recreational or traditional uses. 

Despite its relative isolation, there are many human-mediated and natural pathways by which 
pests, weeds and diseases can spread to and within the Victoria catchment. New pests, weeds and 
diseases may spread from adjacent regions, other parts of Australia or even neighbouring 
countries. Biosecurity is a shared responsibility that requires governments, industries and the 
community to each take steps to limit the introduction and spread of pests, weeds and diseases, 
to detect and respond to incursions and to manage the impacts of key biological threats. 

A variety of current and potential pests, weeds and diseases could have an impact on irrigated 
cropping in the Victoria catchment. These include fall armyworm (Spodoptera frugiperda, which 
consumes C4 grass crops), cucumber green mottle mosaic virus (Tobamovirus), which infects a 
wide range of cucurbit crops), incursion risks from overseas, such as citrus canker (Xanthomonas 
citri subsp. citri), exotic fruit flies, and parthenium weed (Parthenium hysterophorus) (as a 
competitor, contaminant and allergen). Farm biosecurity planning to identify, prevent, detect and 
manage key pest, weed and disease threats is fundamental to a successful enterprise. Such 
planning includes following government and industry best practice regarding movement of plants, 
plant products and machinery, control of declared species, pesticide use, farm stewardship and 
market access requirements. 

Preventive biosecurity practices are crucial in aquaculture facilities as diseases can be difficult to 
eliminate. There are many diseases of production concern, whether overseas, having entered 
Australia (e.g. white spot syndrome virus of crustaceans) or naturally occurring in Australian 
ecosystems. Aquaculture biosecurity planning needs to consider hygiene actions needed for key 
pathways of disease entry, early detection and diagnosis, quarantining and treatment. 

Invasive species, whether pest, weed or disease, are commonly characterised as occurring across 
multiple land uses in a landscape. Their impacts will vary between land uses, but their coordinated 
control requires action across all tenures. There are various high-impact weeds declared in the NT 
that are present in or threaten to invade the Victoria catchment, including aquatic plants, grasses, 
shrubs and trees. There are also pest vertebrates (e.g. large feral herbivores, exotic fish), pest 
invertebrates (e.g. exotic ants) and plant diseases (e.g. Phytophthora spp.). NT Government legal 
requirements to control declared pests, weeds and diseases need to be followed. Regional and 
local irrigation and industry infrastructure development, including road networks, should include 
prevention and management of invasive species in their environmental planning processes. Choice 
of crops and aquaculture species should also consider their invasive risk and any management 
required to prevent their spread into the environment. 


Off-site and downstream impacts 

Agriculture can affect the water quality of downstream freshwater, estuarine and marine 
ecosystems. The principal pollutants from agriculture are nitrogen, phosphorus, total suspended 
solids, herbicides and pesticides. Most of the science in northern Australia concerned with the 
downstream impacts of agricultural development has been undertaken in the eastern-flowing 
rivers that flow into the Great Barrier Reef lagoon. Comparatively little research on the topic has 
been done in the rest of northern Australia. 

Degraded water quality can cause a loss of aquatic habitat, biodiversity, and ecosystem services. 
Increased nitrogen and phosphorus can cause plankton blooms and weed infestation, increase 
hypoxia (low oxygen levels) and result in fish deaths. Pesticides, used to increase agricultural 
productivity, can harm downstream aquatic ecosystems, flora and fauna. As with fertiliser 
nutrients, pesticides can enter surface water bodies and groundwater via infiltration, leaching, and 
runoff from rainfall events and irrigation. 

Losses via runoff or deep drainage are the main pathways by which agricultural pollutants enter 
water bodies. Management of irrigation or agricultural drainage waters is a key consideration 
when evaluating and developing new irrigation systems, and it should be given careful 
consideration during the planning and design process. Seasonal hydrology, particularly ‘first-flush’ 
events following irrigation or significant rainfall, plays a critical role in determining water quality. 
Studies have shown that pesticide concentrations in runoff are highest following initial irrigation 
events but decrease in subsequent events. Similarly, nitrogen concentrations in runoff are often 
higher following early-season rainfall, when crops have not yet fully absorbed available nitrogen, 
leading to increased transport in runoff. Minimising drainage water by using best-practice 
irrigation design and management should be a priority in any new irrigation development in 
northern Australia. 

While elevated contaminants and water quality parameters can harm the environment and human 
health, there are several processes by which aquatic ecosystems can partially process 
contaminants and regulate water quality. Denitrification is a naturally occurring process that can 
remove and reduce nitrogen concentrations within a water body. Phosphorus, however, does not 
have a microbial reduction process equivalent to denitrification. Instead, if it is not temporarily 
taken up by plants, phosphorus can be adsorbed onto the surface of inorganic and organic 
particles and stored in the soil, or deposited in the sediments of water bodies, such as wetlands. 

Aquaculture can be impacted by poor water quality and can also contribute to poor water quality 
unless aquaculture operations are well managed. Aquaculture species are particularly vulnerable 
to some of the insecticides and other chemicals used in agricultural, horticultural and mining 
sectors, and in industrial and domestic settings. Aquaculture management is designed to discharge 
water that contains low amounts of nutrients and other contaminants. The aim is for discharge 
waters to have similar physiochemical parameters to the source water. Because aquaculture 
management in northern Australia has largely been developed to ensure that the waters of the 
Great Barrier Reef lagoon do not receive excessive contaminants they typically operate under 
world’s best practice. 


Irrigation-induced salinity 

Naturally occurring areas of salinity or ‘primary salinity’ occur in the landscape, with ecosystems 
adapted to the saline conditions. Any change to landscape hydrology, including clearing and irrigation, 
can mobilise salts, resulting in environmental degradation in the form of ‘secondary salinity’. Rising 
groundwater can mobilise salts in the soil and substrate materials, moving the salts into the plant 
root zone and/or discharging salts on lower slopes, in drainage depressions or in nearby streams. 
Soil knowledge and best-practice management of irrigation timing and application rates can 
reduce the risk of irrigation-induced salinity. 

It should be noted that the material in this chapter provides general information regarding soils 
suitable for irrigation development. The risk of secondary salinisation at a specific location in the 
Southern Gulf catchments can only be properly assessed by undertaking detailed field 
investigations at a local scale. 

Existing salinity is not prominent in the Assessment area apart from the salt plains along the coast, 
which are not considered for irrigation development. However, the cracking clay soils on the 
Armraynald Plain, particularly the black soils along the Gregory River backplain, have subsoils that 
are high in salt and susceptible to irrigation-induced secondary salinity. These cracking clay soils 
can be successfully irrigated if they can be managed to prevent waterlogging and the mobilisation 
of salts in the profile. The clay soils (SGG 9) on the Barkly Tableland have low subsoil salt levels. 
Where they are underlain by porous limestone and dolomite, a build-up of salts due to irrigation is 
not expected. 

The sandy, loamy and sand or loam over friable brown, yellow and grey clay soils on the 
Doomadgee Plain also have negligible salts within the soil profile. However, due to other risk 
factors, care would need to be exercised when clearing the silver box, bloodwood and broad-leaf 
paperbark savanna landscapes for rainfed or irrigated cropping. Groundwater aquifers contained 
by underlying ferricrete, the likelihood of soils having variable depths, and the very gently 
undulating plain make it difficult to manage irrigation water discharge on lower slopes and in 
drainage depressions, causing salts to accumulate in these areas in the long term. In places where 
these soils are shallow, it would be necessary to monitor the depth of watertables and manage 
irrigation rates accordingly. In addition, over-irrigation is likely to have off-site impacts in the long 
term, as the lateral flow of water can ‘wick’ from the lower slopes in these landscapes to form 
scalds. From these scalds, salts can potentially be mobilised towards nearby streams. 

7.2 Introduction 

Water and irrigation development can result in complex and in some cases unpredictable changes 
to the surrounding environment. For instance, before the construction of the Burdekin Falls Dam, 
the Burdekin Project Committee (1977) and Burdekin Project Ecological Study (Fleming et al., 
1981) concluded that the dam would improve water quality and clarity in the lower river and that 
para grass (Brachiaria mutica), an invasive weed from Africa that was then present at relatively 
low levels, could become a useful ecological element as a result of increased water delivery to the 
floodplain. However, the Burdekin Falls Dam has remained persistently turbid since construction in 
1987, greatly altering the water quality and ecological processes of the river below the dam and 
the many streams and wetlands into which that water is pumped on the floodplain (Burrows and 


Butler, 2007). Para grass and more recently hymenachne (Hymenachne amplexicaulis), a plant 
from South America, have become serious weeds of the floodplain wetlands, rendering these 
wetlands unviable as habitat for most aquatic biota that formerly occurred there (Perna, 2003, 
2004; Tait and Perna, 2000). 

Thus, there are limitations to the level of advice that can be provided in the absence of specific 
development proposals, so this section provides general advice on those considerations or 
externalities that are most strongly affected by water resource and irrigation developments. It is 
not possible to discuss every potential change that could occur. In particular, the ecological 
impacts of vegetation clearing associated with irrigated agriculture are not explicitly examined as 
it is considered of secondary concern to potential impacts on water dependent ecological assets. 
This is because irrigated agriculture occupies a very small proportion of the landscape (typically 
less than 1%) but can result in a disproportionately high degree of regulation of river flow. 
Consequently, the Assessment placed greatest effort in understanding the potential ecological 
impacts of changes in streamflow on aquatic dependent ecosystems. It is noted, however, that 
areas of high agricultural potential may also be highly valued with respect to biodiversity 
conservation (Kutt et al., 2009). For these and other reasons the northern jurisdictions have formal 
processes in place for the approval (or not) of clearing native vegetation. Clearing approvals are 
only provided by the jurisdictions where they consider the ecological impact to be minimal given 
the extent and protection of vegetation type in the region. 

The remainder of the chapter is structured as follows: 

•Section 7.3 Ecological implications of altered flow regimes: examines how river regulationaffects inland and freshwater assets in the Victoria catchment and marine assets in the near-
shore marine environment. It also examines how the impacts can be mitigated.
•Section 7.4 Biosecurity considerations: discusses the risks presented to an irrigationdevelopment by diseases, pests and weeds, and the risks new agriculture or aquacultureenterprise in the Victoria catchment may present to the wider industry and broader catchment.
•Section 7.5 Off-site and downstream impacts: considers how agriculture can affect the waterquality of downstream freshwater, estuarine and marine ecosystems.
•Section 7.5 Irrigation-induced salinity: briefly discusses the risk of irrigation-induced salinity toan irrigation development and the downstream environment in the Victoria catchment.


It should be noted that the discussions in section 7.4 to 7.5 are more generalised in nature than 
the material presented in Section 7.3, as the actual risks tend to be highly scenario- and location-
specific, and appropriate data are typically missing. 

Other externalities associated with water resource and irrigation development discussed 
elsewhere in this report include the direct impacts of the development of a large dam and 
reservoir on: 

•Indigenous cultural heritage (Section 3.4)
•the movement of aquatic species and loss of connectivity (Section 5.4)
•terrestrial ecosystems within the reservoir inundation area (Section 5.4).


These externalities are rarely factored into the true costs of water resource or irrigation 
development. Even in parts of southern Australia, where data are more abundant, it is very 


difficult to express these costs in monetary terms, as the perceived changes are strongly driven by 
values, which can vary considerably within and between communities and fluctuate over time. 
Therefore, the material in this chapter is presented as a stand-alone analysis to help inform 
conversations between communities and government, and subsequent decisions. 

It is important to note that this chapter primarily focuses on key risks resulting from irrigated 
agriculture and to a lesser extent aquaculture, although the section on biosecurity considers both 
risks to the enterprise and risks emanating from the enterprise into the broader environment. 
Additional risks to irrigated agriculture and aquaculture are discussed elsewhere in this report, 
including risks associated with: 

•flooding (Section 2.5)
•sediment infill of large dams and reservoir inundation (Section 5.4)
•reliability of water supply (sections 5.4 and 6.3)
•timing of runs of failed years on the profitability of an enterprise (Section 6.3).


The material within this chapter is largely based on the companion technical reports on ecology 
asset analysis (Stratford et al., 2024a) but also draws upon findings presented in the Northern 
Australia Water Resource Assessment technical reports on agricultural viability (Ash et al., 2018) 
and aquaculture viability (Irvin et al., 2018). Further information can be found in those reports. 

7.3 Ecological implications of altered flow regimes 

7.3.1 Water resource development and flow ecology 

The ecology of a river is intricately linked to its flow regime, with species broadly adapted to the 
prevailing conditions under which they occur. Flow-dependent flora, fauna and habitats are 
defined here as those sensitive to changes in flow and those sustained by either surface water or 
groundwater flows or a combination of these. In rivers and floodplains, the capture, storage, 
release, conveyance and extraction of water alters the environmental template on which the river 
functions, and water regulation is frequently considered one of the biggest threats to aquatic 
ecosystems worldwide (Bunn and Arthington, 2002; Poff et al., 2007). Water resource 
development can act during both wet and dry periods to change the magnitude, timing, duration 
and frequency of flows (Jardine et al., 2015; McMahon and Finlayson, 2003). Impacts on fauna, 
flora and habitats associated with flow regime change often extend considerable distances 
downstream from the source of the impacts and into near-shore coastal and marine areas as well 
as onto floodplains (Burford et al., 2011; Nielsen et al., 2020; Pollino et al., 2018). Water resource 
development can also result in changes to water quality (see Section 7.5). 

The environmental risks associated with water resource development are complex, and 
particularly so in northern Australia. This is in part because of the diversity of species and habitats 
distributed across and within the catchments and the near-shore marine zones, and because 
water resource development can produce a broad range of direct and indirect environmental 
impacts. These impacts can include changes to flow regime, loss of habitat, loss of function such as 
connectivity, changes to water quality, and the establishment of pest species. Instream dams 
create large bodies of standing water that inundate terrestrial habitat and result in the loss of the 


original stream and riverine conditions (Nilsson and Berggren, 2000; Schmutz and Sendzimir, 
2018). Storages can capture flood pulses and reduce the volume and extent of water that 
transports important nutrients into estuaries and coastal waters via flood plumes (Burford and 
Faggotter, 2021; Burford et al., 2016; Tockner et al., 2010). Further, even minor instream barriers 
can disrupt migration and movement pathways, causing loss of essential habitat for species that 
need passage along the river at key times, and fragmentation of populations (Crook et al., 2015; 
Pelicice et al., 2015). With water resource development and irrigation comes increased human 
activity. This can add additional pressures, including changes in fire regimes, additional harvesting 
pressures, and biosecurity risks associated with invasive or pest species transferring into new 
habitats or increasing their advantage in modified habitats (Pyšek et al., 2020). 

Section 7.3 of this report analyses the risks to flow-dependent freshwater, estuarine and near-
shore marine assets, as well as terrestrial systems, resulting from changes in the flow regime 
change in the catchment of the Victoria River. See the companion technical report on water 
storages (Yang et al., 2024) for more details on the impacts of habitat loss within potential dam 
impoundments and connectivity loss due to the development of new instream barriers. Refer to 
the companion technical report on ecological asset descriptions in the Victoria catchment by 
Stratford et al. (2024a) for more details on the flow ecology of the Victoria catchment and its 
ecological values. The asset description report (Stratford et al., 2024a) also qualitatively examines 
existing and potential threatening processes for freshwater-dependent ecological assets, including 
possible influences of synergistic impacts. For more details of the ecological asset analysis and 
details of analysis for all assets, see Stratford et al. (2024b). 

7.3.2 Ecology of the Victoria catchment 

The comparatively intact landscapes of the Victoria catchment hold significant ecological and 
environmental values and are important for the ecosystem services they provide, including 
recreational activities, tourism, fisheries (Indigenous, recreational and commercial), military 
training, and agricultural production (notably cattle grazing on native pastures). The Victoria River 
is a large river originating to the south of the Judbarra National Park. At over 500 km in length, it is 
the second longest rivers in the NT with permanent water. The catchment area of 82,400 km2 
makes it one of the largest ocean-flowing catchments in the NT, with flows that enter the south-
eastern edge of the Joseph Bonaparte Gulf. The catchment and the surrounding marine 
environment contain a rich diversity of important ecological assets, including species, ecological 
communities, habitats, and ecological processes and functions. The ecology of the Victoria River is 
maintained by its flow regime, shaped by the catchment’s complex geomorphology and 
topography, and driven by patterns of seasonal rainfall, evapotranspiration, and groundwater 
discharge. 

The protected areas located in the Victoria catchment include one gazetted national park 
(Judbarra), a proposed extension to an existing national park (Keep River), the Commonwealth 
Joseph Bonaparte Gulf Marine Park, two Indigenous Protected Areas and two Directory of 
Important Wetlands in Australia (DIWA) sites. The two DIWA sites are the Bradshaw Field Training 
Area and the Legune Wetlands (Figure 7-2). The freshwater sections of the Victoria catchment 
include diverse habitats such as intermittent and perennial rivers, anabranches, wetlands, 
floodplains, and groundwater-dependent ecosystems (GDEs). The diversity and complexity of the 


habitats, and the connections between the habitats within a catchment, are vital for providing the 
range of habitats needed to support both the aquatic and terrestrial biota (Schofield et al., 2018). 

In the wet season, flooding connects rivers to floodplains. This exchange of water means that 
floodplain habitats support higher levels of primary and secondary productivity than surrounding 
terrestrial areas with less frequent inundation (Pettit et al., 2011). Infiltration of water into the soil 
during the wet season and along persistent streams enables riparian habitats to form an important 
interface between the aquatic and terrestrial environments. While riparian habitats often occupy a 
relatively small proportion of the catchment, they frequently have a higher species richness and 
abundance of individuals than surrounding habitats. The riparian habitats that fringe the rivers and 
streams of the Victoria catchment have been rated as having moderate to high cover and 
structural diversity of riparian vegetation (Kirby and Faulks, 2004). These riparian habitats 
comprise a Eucalyptus camaldulensis overstorey with Lophostemon grandiflorus, Terminalia 
platyphylla, Pandanus aquaticus and Ficus spp understorey. The dominant overstorey across many 
parts of the catchment includes Acacia holosericea and Eriachne festucacea (Kirby and Faulks, 
2004). Further away from the creeks and rivers, the overstorey vegetation in the Victoria 
catchment becomes sparser, opening up into savanna woodlands and various grasslands. 

In the dry season, biodiversity is supported by perennial rivers, wetlands and the inchannel 
waterholes that persist in the landscape. In ephemeral rivers, the waterholes that remain become 
increasingly important as the dry season progresses; they provide important refuge habitat for 
species and enable recolonisation into surrounding habitats upon the return of larger flows 
(Hermoso et al., 2013). Waterholes provide habitat for water-dependent species, including fish, 
sawfish and freshwater turtles, and also provide a source of water for other species more broadly 
within the landscape (McJannet et al., 2014; Waltham et al., 2013). 

The mouth and estuary of the Victoria River is up to 25 km wide and includes extensive mudflats 
and mangrove stands (Kirby and Faulks, 2004). Although mangroves and mudflats are prominent 
along the coastal margins (Department of Climate Change, Energy, the Environment and Water, 
n.d.), the mangrove communities along the estuary are recognised as being low in speciesrichness, with approximately ten plant species recorded. Of these, the dominant mangrove speciesin the catchment is Avicennia marina, which is largely confined to the estuary (Kirby and Faulks,
2004). The Legune (Joseph Bonaparte Bay) Important Bird and Biodiversity Area can support over15,000 waterbirds across mudflats, salt flats, and seasonally inundated wetlands (BirdLifeInternational, 2023). Marine habitats in northern Australia are vital for supporting importantfisheries, including banana prawn (Fenneropenaeus merguiensis), mud crab (Scylla spp.) andbarramundi (Lates calcarifer), as well as for supporting biodiversity more generally, includingwaterbirds, marine mammals and turtles. In addition, the natural waterways of the sparselypopulated catchments support globally significant stronghold populations of endangered andendemic species that often use a combination of both marine and freshwater habitats (e.g. sharksand rays).


7.3.3 Scenarios of hypothetical water resource development and future climate 

This ecology analysis used modelled hydrology to explore the potential ecological risks of water 
resource development in the Victoria catchment through a series of hypothetical scenarios. It used 
a purpose built river model for the Victoria catchment – for more detail, see the companion 
technical report on river model calibration in the Victoria catchment by Hughes et al. (2024a). The 
scenarios were designed to explore how different types and scales of water resource development 
might affect selected water-dependent ecosystems across the Victoria catchment. 

The hypothetical developments assessed included instream infrastructure (i.e. large dams) and 
water harvesting (i.e. pumping river water into offstream farm-scale storages). In evaluating the 
likelihood of a development scenario occurring, Section 1.2.2, which discusses the plausibility of 
development pathways, should be consulted. Broad scenario definitions used in the Assessment 
are described in Section 1.4.3, with Table 7-1 providing a summary of the specific scenarios used in 
the ecology analysis. Figure 7-2 shows the location of the river system model nodes used in the 
ecology analysis and the location of hypothetical water resource developments. Further details of 
the river system model simulations are provided in the companion technical report on river model 
simulation (Hughes et al., 2024b). The river models were also used to explore the ways in which 
dry future climate conditions may have an impact on water-dependent ecosystems (i.e. Scenario 
C), as well as the interactions between water resource development and a potential dry climate 
future (i.e. Scenario Ddry). 

Key terms used in Section 7.3 

Water harvesting – an operation where water is pumped or diverted from a river into an 
offstream storage, assuming there are no instream structures 

Offstream storages – usually fully enclosed circular or rectangular earthfill embankment 
structures situated close to major watercourses or rivers so as to minimise the cost of pumping 

Large engineered instream dams – usually constructed from earth, rock or concrete materials as a 
barrier across a river to store water in the reservoir created. In the Victoria catchment, most 
hypothetical dams were assumed to be concrete gravity dams with a central spillway (see 
companion technical report on water storage) (Yang et al., 2024) 

Annual diversion commencement flow requirement (DCFR) – also known as an end-of-system 
requirement, the cumulative flow that must pass the most downstream node (81100000) during a 
water year (1 September to 31 August) before pumping can commence. It is usually implemented 
as a strategy for mitigating the ecological impact of water harvesting 

Pump-start threshold – a daily flow rate threshold above which pumping or diversion of water can 
commence. It is usually implemented as a strategy for mitigating the ecological impact of water 
harvesting 

Pump capacity – the capacity of the pumps, expressed as the number of days it would take to 
pump the entire node irrigation target 

Reach irrigation volumetric target – the maximum volume of water extracted in a river reach over 
a water year. Note, the end use is not necessarily limited to irrigation. Users could also be involved 
in aquaculture, mining, urban, or industrial activities 


System irrigation volumetric target – the maximum volume of water extracted across the entire 
study area over a water year. Note, the end use is not necessarily limited to irrigation. Users could 
also be involved in aquaculture, mining, urban, or industrial activities 

Transparent flow – a strategy for mitigating the ecological impacts of large instream dams by 
allowing all reservoir inflows below a flow threshold to pass ‘through’ the dam 

Note that each potential water resource development pathway results in different changes to the 
flow regimes, due to differences and interactions between rainfall and upstream catchment sizes, 
inflows, the attenuation of flow through the river system (including accumulating inflows with 
river confluences), and the many ways in which each hypothetical water resource development is 
implemented. These scenarios were not analysed because they are considered likely or 
recommended by CSIRO; rather, they were selected to explore some of the interactions between 
location and the types and scales of development, to provide insights into how different types and 
scales of water resource development may influence ecology outcomes across the catchment. 

Some of the hypothetical scenarios listed in Table 7-1 do not provide dedicated environmental 
provisions and have been optimised for water yield reliability, without considering policy settings 
or additional restrictions that may help mitigate the impacts to water-dependent ecosystems. 
These scenarios are useful for considering impacts across various development strategies in the 
absence of mitigation strategies or policy settings (or could be representative of regulatory non-
compliance). Further, as an artefact of the scenario assumptions, modelling hypothetical dam 
development assumed water from the reservoir was released via a pipe or channel rather than 
releasing water for irrigation into the downstream river channel. Consequently, the river model 
calculates and removes the extractive take at the dam node. Furthermore, many of the scenarios 
explored, while technically feasible, exceed the level of development that would be likely to 
reasonably occur and are modelled without regulatory requirements and management to mitigate 
ecological impacts. These scenarios were included as a stress test of the system and can be useful 
for benchmarking or contrasting various levels of change and different mitigation options. 

The development scenarios are hypothetical and are for the purpose of exploring a range of 
options and issues in the Victoria catchment. In the event of any future development occurring, 
further work would need to be undertaken to assess environmental impacts associated with the 
specific development across a broad range of environmental considerations. 


 

For more information on this figure please contact CSIRO on enquiries@csiro.au
Figure 7-2 Map of the Victoria catchment and the marine region showing the locations of the river system modelling 
nodes at which flow–ecology dependencies were assessed (numbered) and the locations of hypothetical water 
resource developments 

Nodes are the locations at which flow–ecology dependencies were assessed and are marked as purple or orange 
circles. The hypothetical modelled dam locations are shown by the triangles marked A and B, and the water harvesting 
extraction locations are shown by orange circles. The flow ecology of the ecological assets was assessed in the 
subcatchments in which they occur, downstream of the river system nodes. The locations of ecological assets across 
the catchment for modelling are documented in Stratford et al. (2024b). 


Table 7-1 Water resource development and climate scenarios explored in the ecology analysis 

Descriptions of the river system modelling scenarios are provided in Hughes et al. (2024b). DCFR = annual diversion 
commencement flow requirement. FSL = full supply level. GCM = general circulation model. na = not applicable. 

SCENARIO 

DESCRIPTION 

TRANSPARENT 
FLOW 

ANNUAL 
TARGET 
EXTRACTION 
VOLUME / 
YIELD (GL) 

DCFR (GL) 

PUMP-START 
THRESHOLD 
(ML/D) 

PUMP 
CAPACITY 
(D) 

Scenario A 

Historical climate and current 
levels of development 

 

 

 

 

 

A 

Historical climate and no 
development 

No 

0 

0 

na 

na 

Scenario B 

Historical climate and 
hypothetical future 
development 

 

 

 

 

 

B-DLC 

Single dam on Leichhardt Creek 

No 

60‡ 

na 

na 

na 

B-DVR 

Single dam on Victoria River 

No 

500‡ 

na 

na 

na 

B-D2 

Two hypothetical dams, LC, VR 

No 

560‡ 

na 

na 

na 

B-WV, EF, PT, CR 

Water harvesting with varying 
target extraction volume (V), 
DCR requirements (F), pump-
start threshold (T), and/or 
pump rate (R) 

na 

V = 40, 80, …, 
960, 1000‡ 

F = 0, 200, 500, 
700, 1000 

T = 200, 300, 
…, 900, 1000 

R = 10, 20, 
30, 40, 50 

Scenario C 

Future climate and current 
level of development 

 

 

 

 

 

Cdry 

Dry GCM§ projection (see 
Section 2.4.5) 

No 

0 

na 

na 

na 

Scenario D 

Future climate and 
hypothetical future 
development 

 

 

 

 

 

D-D2 

Two hypothetical dams (same 
as B-D2), for each Scenario C 
climate (clim = dry) 

No 

591‡ 

na 

na 

na 

D-D2T 

Two hypothetical dams (same 
as B-D2), for each Scenario C 
climate (clim = dry) with 
transparent flows 

Yes 

591‡ 

na 

na 

na 

D-W150,F,600,c 

Water harvesting under 
Scenario C climate (clim = dry) 

na 

680‡ 

0 

200 

30 



‡Target extraction volume applies to water harvesting scenarios. Yield applies to hypothetical dam scenarios and is the amount of water that could 
be supplied by the dams reservoir in 85% of years. 

7.3.4 Ecology outcomes and implications 

The ecology activity used an asset-based approach for analysis and built upon work presented in 
Pollino et al. (2018) and Stratford et al. (2024c). For the Victoria catchment, 18 ecological assets 
were selected for analysis (Table 7-2) across 41 nodes, including the end-of-system node for 
marine assets (Figure 7-2). Both the ecology asset descriptions technical report (Stratford et al., 
2024a) and the ecology asset analysis technical report (Stratford et al., 2024b) should be consulted 
in conjunction with the material provided here. 


The selected ecological assets spanned freshwater, marine and terrestrial habitats and included 
species, species groups, and habitats that depend on river flows. Eighteen assets (shown in 
Table 7-2) were modelled to investigate the effects of changes to river flow resulting from 
hypothetical water resource development and a projected dry future climate (as a potential worst-
case projected climate scenario). Assets were included if they were distinctive, representative, 
describable and significant within the catchment. The flow–ecology interactions of the assets, 
including important flow linkages and relationships, and assessment locations in the catchment 
were documented in Stratford et al. (2024a), as were species and habitat distribution maps, 
including species distribution models developed for many of the species. Each asset had different 
requirements of, and linkages to, the flow regime and was distributed across particular parts of 
the catchment or the near-shore marine zone. Understanding the flow–ecology interactions of 
assets and their locations across the catchment was important for identifying the potential risks 
caused by changes in catchment hydrology. 

Table 7-2 Ecological assets used in the Victoria Water Resource Assessment 

Eighteen ecological assets were modelled in the ecology analysis. A description of the ecological assets, their flow 
ecology, and their distribution is provided in Stratford et al. (2024a). Assets marked with an asterisk are presented in 
this report. The analyses and interpretations for all assets are provided in Stratford et al. (2024b). 

For more information on this figure, table or equation please contact CSIRO on enquiries@csiro.au.
The flow dependencies (hydrometrics) modelling calculated for each asset an index of flow regime 
change resulting from the different scenarios using a suite of asset-specific hydrometrics, with 
metrics based upon those in Kennard et al. (2010). Hydrometrics are statistical measures of the 
long-term flow regime and can include aspects of flow magnitude, duration, timing, frequency and 


rate of change (Kennard et al., 2010). As a basis for selecting asset hydrometrics, Stratford et al. 
(2024a) details each asset’s ecology and relationship to flow, including: 

• habitat dependencies (e.g. floodplain inundation, refuge, recharging of groundwater) 
• life-cycle processes (e.g. flow to trigger spawning) 
• migration and movement pathways (e.g. high flows to enable migration into floodplain wetlands 
and along the river) 
• flow to support productivity and food resources (e.g. nutrient plumes into coastal areas). 


Hydrometrics were calculated for each node under each scenario and used to quantify relative 
change in important parts of the flow regime as percentile change relative to the distribution of 
annual values of Scenario A, calculated over the Assessment period (i.e. 1 September 1890 to 
31 August 2022). The hydrometric index of change is calculated as: 
𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃𝑃 𝑐𝑐ℎ𝑎𝑎𝑎𝑎𝑎𝑎𝑎𝑎=
𝑥𝑥−𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠 𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚
𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠𝑠 𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚𝑚 
× 100 

Where x is the median of metric i, for the hypothetical scenario, and all values are for individual 
nodes. 

The assets’ important metrics are combined by averaging, with each metric being weighted, 
considering the knowledge base to support it and its significance to the asset’s ecology. The 
percentile change is weighted downstream of nodes by the habitat value of each reach in which 
the asset occurs based upon results of species distribution models, and the change in flow 
dependency is calculated for each node. The species distribution models were developed using a 
combination of Random Forests, Generalised Linear Models (GLMs), and Maxent algorithms (see 
Stratford et al., 2024a). These models were applied to a 2.5 km buffer surrounding the rivers 
within the catchment to quantify habitat suitability. The change in the flow dependencies was 
weighted by habitat suitability for each asset between the river system model nodes of each river 
reach. As such, river reaches with important asset habitat quality or values are weighted higher 
than marginal habitat. Aggregation of these weighted flow dependency values is undertaken to 
calculate the catchment means of asset–flow dependencies from the individual node values (see 
Stratford et al., 2024b for more details). 

Hydrometrics have been broadly used in ecohydrology assessments in national and international 
contexts for a range of purposes, including water allocation planning, and in ecohydrology 
research and literature (Leigh and Sheldon, 2008; Marsh et al., 2012; Olden and Poff, 2003). For 
this analysis, the flow dependencies modelling considered reach- and catchment-wide changes in 
the assets’ important flow dependencies across the subcatchments in which the assets occur, 
including the near-shore marine zone. The impact of a hypothetical development on water-
dependent ecological assets is inferred and reported here in terms of a habitat-weighted 
percentile change in asset-specific important flow dependencies. 

For interpretation of the results, larger values represent greater change in the parts of the flow 
regime and across sections of the catchment that are important for the asset, with qualitative 
descriptors provided in Table 7-3 considering the habitat weighted value of each reach for each 
asset. At a single location as the values are percentile change from the median of the distribution 
of Scenario A, the assets flow dependency values can be referenced against this historical 
variability. For example, a value of 25 for a metric at a single location represents a change from 


the median (50th percentile of the historical distribution) to the 25th percentile. Using mean 
annual flow as an example metric, the value of 25 would represent the scenario median now being 
similar to the driest 25% of years for this metric. 

Table 7-3 Descriptive qualitative values for the flow dependencies modelling as percentile change of the 
hydrometrics 

Values consider the change in mean hydrometric value against the natural distribution observed in the modelled 
baseline series of 132 years. For more information including metric and habitat weighting see Stratford et al. (2024b). 

VALUE 

RATING 

IMPLICATION 

>0–2

Negligible 

The median for the assets’ metrics under the scenario is negligible change, as 
considered against the modelled historical conditions, and is well within the normal 
experienced conditions at the model node. The assets’ hydrometrics are within the 
2nd percentile of the historical Scenario A median 

2–5 

Minor 

The change is minor, with the median for the assets’ metrics for the scenario 
outside the 2nd and within the 5th percentile of Scenario A and the historical 
distribution of the hydrometrics 

5–15 

Moderate 

The change is moderate, with the median for the assets’ metrics under the scenario 
outside 5th and within the 15th percentile of Scenario A and the historical 
distribution of the hydrometrics 

15–30 

Major 

The change is major, with the median for the assets’ metrics for the scenario 
outside the 15th and within the 30th percentile of Scenario A and the historical 
distribution of the hydrometrics 

>30

Extreme 

The change is extreme, with the median for the assets’ metrics under the scenario 
being extreme change, as considered against the modelled historical conditions, 
with metrics occurring well outside typical conditions at the modelled node or 
exceeding that of historical variability. The scenario median is outside the 30th 
percentile from the historical Scenario A median (or equivalent to the new mean, 
being typical of the outside 20% of observations from the historical sequence across 
the metrics important to the asset) 



In addition to quantifying change relative to the historical variability under Scenario A for each 
asset, an existing analogue of change in asset–flow dependencies is compared using the level of 
change in the hypothetical scenarios with models of the Ord River below Lake Kununurra (with 
and without the Ord River Dam and the Ord Diversion Dam (i.e. Lake Kununurra)), near the end-of-
system. This analogue considers the modelled changes in river flow associated with the 
construction of Lake Kununurra, Ord River Dam and Ord River Irrigation Scheme. In addition to the 
Ord scheme analogue, three natural periods of low-flow conditions are used as benchmarks and 
plotted alongside the hypothetical developments and climate scenario values. For the Victoria 
catchments, these were the periods with the lowest 30-year flow (1905–1934), lowest 50-year 
flow (1890–1939) and lowest 70-year flow (1890–1959) across the historical climate (Scenario A). 
These are benchmark comparisons, so flow conditions and outcomes of change in flow 
dependencies would not necessarily be equivalent to these if development were to occur, but 
they provide a useful comparison of the potential level of change under the scenarios. 

It is important to note that this ecological analysis is broad in scale, and the results include 
significant uncertainty. This uncertainty is due to a range of factors, including, but not limited to, 
incomplete knowledge, variability within and between catchments, and limitations associated with 
modelling processes and data. Furthermore, thresholds, temporal processes, interactions, 
synergistic effects, and feedback responses in the ecology of the system may not be adequately 
captured in the modelling process. There is also uncertainty associated with the projected future 


climates, such as rainfall patterns and any additional synergistic and cumulative threatening 
processes that may emerge and interact across scales of space and time, including the production 
of potentially novel outcomes. The understanding of freshwater ecology in the Victoria catchment 
and northern Australia more generally is still developing. 

Provided below is a sample of outcomes for three representative assets for the Victoria 
catchment: barramundi; shorebirds; and mangroves. For more details and for results on other 
assets see Stratford et al. (2024b). 

Barramundi 

Barramundi are large opportunistic, predatory fish that inhabit riverine, estuarine and marine 
waters in northern Australia, including those in the Victoria catchment. Adults mate and spawn in 
the lower estuary and coastal habitats near river mouths during the late dry season and early wet 
season. Small juveniles migrate upstream from the estuary to freshwater habitats, where they 
grow and mature before emigrating downstream to estuarine habitats as adults, where they 
reside and reproduce. In the Victoria catchment, barramundi occupy relatively pristine habitats in 
both the freshwater and estuarine reaches, as well as in the coastal marine waters. Their life 
history renders them critically dependent on river flows (Tanimoto et al., 2012) as new recruits 
move into supra-littoral estuarine and coastal salt flat habitats, and freshwater riverine reaches 
and wetland habitats occupied as juveniles (Crook et al., 2016; Russell and Garrett, 1983, 1985). 

Barramundi are sensitive to changes in flow regime in Australia’s tropical rivers where critical 
requirements for growth and survival include riverine–wetland connectivity, riverine–estuarine 
connectivity, passage to spawning habitat, and volume of flood flows (Crook et al., 2016; Roberts 
et al., 2019). 

Barramundi are an ecologically important fish species capable of modifying the estuarine and 
riverine fish and crustacean communities throughout Australia’s wet-dry tropics (Blaber et al., 
1989; Brewer et al., 1995; Milton et al., 2005). It is targeted by commercial, recreational and 
Indigenous fisheries. Barramundi is an important species for Indigenous Peoples in northern 
Australia, both culturally (Finn and Jackson, 2011; Jackson et al., 2011) and as a food source 
(Naughton et al., 1986). 

The analysis here considers change in flow regime and related habitat changes. For consideration 
of the addition or loss of potential habitat associated with the creation of a dam impoundment or 
instream structures see Yang et al. (2024). 

Flow dependencies analysis 

Barramundi were modelled across a total of 1918 km of assessment reaches in the Victoria 
catchment and in the marine region, with contributing flows from a total of 41 model nodes (see 
Stratford et al. (2024b)). Some of the key river reaches for barramundi within the catchment were 
modelled downstream of nodes 81100070, 81100000 and 81100002. The locations for modelling 
barramundi in the Victoria catchment were based upon species distribution models (Stratford et 
al., 2024a). 

Hypothetical water resource development in the Victoria catchment resulted in varying levels of 
change to important flow dependencies for barramundi. When considering mean change in flow 
dependencies across all 41 barramundi reaches and nodes, the effects under the hypothetical dam 


scenarios ranged from negligible (0.5) to minor (3.2) under scenarios B-DLCT and B-D2, respectively, 
while for water harvesting the effects were negligible (0.1 to 1.0) under scenarios B-Wv80t200r30f500 
and B-Wv800t200r30f0 (



For more information on this figure please contact CSIRO on enquiries@csiro.au
Figure 7-3 Habitat weighted change in important flow dependencies for barramundi by scenario across model 
nodes 

Colour intensity represents the level of change occurring in important flow metrics as percentile change from the 
historical conditions weighted by the importance of each reach for barramundi. Equivalent colour intensity (i.e. 
corresponding to the asset flow dependency change value) for the Ord River below Lake Kununurra shown bottom 
right. Scenarios are ordered on the left axis by the magnitude of change with the mean across nodes shown on the 
right axis. Horizontal grey bars and number correspond to the mean change across all model node locations. Only the 
30 highest impact nodes are shown (x-axis). Results under Scenario A corresponding to changes in asset flow 
dependency for the lowest 30-year, 50-year and 70-year time periods provide a reference for the modelled changes 
under different hypothetical development and projected future climate scenarios. EOS = end-of-system. 


The mean change in important flow dependencies for barramundi across the Victoria catchment 
for the lowest 30-year, 50-year and 70-year flows in the historical record are 5, 3.6 and 
3.4 respectively. 

Under Scenario B-DLC, (i.e. a potential dam on Leichhardt Creek without transparent flows) there 
was a negligible mean change in important flow dependencies (1.1) across the 41 barramundi 
assessment nodes. When transparent flows were provided to support environmental functions 
(i.e. Scenario B-DLCT), the change in important flows for barramundi was reduced, remaining 
negligible (0.5). Under Scenario B-DVR greater change relative to Scenario B-DLC was calculated, 
with a minor (2.1) mean change in flow dependencies. This was reduced to negligible (1.3) with 
the provision of transparent flows under Scenario B-DVRT. Under Scenario B-D2, which includes 
both the B-DLC and B-DVR dams, a minor (3.2) mean change in flow dependencies occurred across 
the catchment without transparent flows. This was reduced to negligible (1.8) with the provision 
of transparent flows. Under Scenario B-D2 with multiple dams, there was a greater mean change in 
flow dependencies across the catchment, relative to either of the single dam scenarios. This was 
due to the combined effects on flows downstream of the confluence of the two dams and the 
change in flows affecting a larger portion of the catchment from which flows would be 
impounded. At the end-of-system node 81100000 the mean impact under the hypothetical dam 
scenarios in the Victoria catchment was considerably less than at the end-of-system in the Ord. 

Under Scenario B-D2T, habitat-weighted flow changes for barramundi were greatest at node 
81100063 (Figure 7-3), with a major (20.6) change in flow dependencies at this single node. Nodes 
directly downstream of the dams under scenarios B-DLC and B-DVR resulted in extreme (39.9) and 
major (26.6) change, respectively. These changes were reduced to major (18.8) and moderate 
(11.4) with the provision of transparent flows. This reflects a combination of the higher level of 
change in flows directly downstream of dams, the benefits associated with the provision of 
transparent flows for riverine resident species, and the importance for barramundi of the habitat 
at these locations. In years of natural low flows, or flows reduced by anthropogenic activity, the 
range of facultative habitat and ecosystem processes available to barramundi is reduced, reducing 
growth and survival (Blaber et al., 1989; Brewer et al., 1995; Milton et al., 2005). 


 

For more information on this figure please contact CSIRO on enquiries@csiro.au
Figure 7-4 Spatial heatmap of change in important flow dependencies for barramundi, considering their distribution 
across the catchment 

Scenarios are: (a) B-Wv80t200r30f0, (b) B-Wv160t200r30f0, (c) B-W160t60r20f0, (d) B-DLC, (e) Cdry and (f) D-dryw160t200r30. See 
Table 7-1 for a description of the scenarios. River shading indicates the level of flow change of important metrics, 
weighted by the habitat value of each reach for barramundi. 


Under the hypothetical water harvesting scenarios, there was a negligible (0.1 to 1.0) mean 
change in flow dependencies across the barramundi assessment nodes for B-Wv80t200r30f500 and 
B-Wv800t200r30f0, respectively. Under the water harvesting scenarios the greatest mean changeoccurred at node 81100001, with a moderate (11.8) change occurring at this node under ScenarioB-Wv800t200r30f0. The change in barramundi flow dependencies with water harvesting variesaccording to the extraction targets, pump-start thresholds, pump rates, and locations (Figure 7-3).
With a low extraction target of 80 GL under Scenario B-Wv80t200r30f0, the mean weighted changeacross the catchment was negligible (0.3), only increasing to 1.0 with the larger extraction targetof 800 GL under Scenario B-Wv800t200r30f0. Increasing the pump-start threshold from 200 to 600 MLper day (scenarios B-Wv160t200r30f0 and B-Wv160t600r30f0) with a target extraction volume of 160 GLmaintained a negligible change with the mean weighted change reduced from 0.4 to 0.3(Figure 7-3). Increasing the pump-start threshold protected the low flows that are important forbarramundi ecology, such as habitat connectivity and pool refugia water quality, particularly at theend of the annual dry season (Arthington et al., 2005; Crook et al., 2022).

The effects of water harvesting were strongly influenced by the node location, relative to the 
extraction. Nodes downstream of multiple water harvesting locations often had large changes in 
important flow dependencies (see node 81100001 compared with node 81101135 in Figure 7-5). 
The benefits associated with having a low system allocation target can be seen when changes in 
flow dependencies are increased with greater allocation targets (see also nodes 81100001 and 
81100180 in Figure 7-5, where change is increased along the plot’s y-axis). Similarly, reductions in 
change can be seen in association with having higher pump-start thresholds (see node 81101135, 
where the change in flow dependencies is reduced along the plot’s x-axis). Figure 7-5 
demonstrates the large spatial variability in risks associated with water harvesting across the 
catchment, and that mitigation strategies can be used to reduce flow change, although their 
success may have local considerations. 




For more information on this figure please contact CSIRO on enquiries@csiro.au
Figure 7-5 The change in barramundi flow dependencies under the various water harvesting scenarios at sample 
nodes across the catchment, showing response to system targets and pump-start thresholds 

Colour intensity represents the level of change occurring in the barramundi’s important flow metrics under the 
scenarios at the important nodes. The results incorporate the habitat-weighted change under each scenario relative to 
the distribution under Scenario A, with results for no end-of-system (EOS) requirement and a pump rate of 30 days. 




Scenario Cdry resulted in a moderate mean change in flow dependencies (5.1) for barramundi 
across the 41 barramundi assessment nodes (Figure 7-3). This level of change accrued, as the new 
median conditions under this scenario were equivalent to the lowest 30-year flow analogue period 
for barramundi (Figure 7-3). This analysis indicates that under Scenario Cdry and under the lowest 
30-year, 50-year and 70-year flow periods there were on average across all catchment nodesgreater changes to mean asset flow dependencies than under scenarios B-D2T (negligible; 1.8) andB-Wv160t200r30f0 (negligible; 0.4). However, it is important to note that local changes under somewater resource development scenarios can be considerably higher. Under scenarios Dclim-D2T andDdry-Wv160t200r30, there were moderate (7.2 and 5.2) changes, respectively, when weighted acrossall barramundi assessment nodes. These values were higher than any of the analogue low-flowperiods. This shows that the combined impacts under scenarios Dclim-D2T or Ddry-Wv160t200r30 weregreater than under Scenario Cdry or under either scenarios B-D2 or B-Wv160t200r30 alone.

Barramundi populations depend on habitat connectivity being maintained throughout the 
catchment. Access to riverine habitats due to the physical barriers of instream infrastructure 
(particularly under scenarios B-DVR or B-D2) would limit access to some habitats (see Yang et al. 
(2024)). Access to upstream habitats and estuarine supra-littoral habitats would be reduced if 
water harvesting or dam scenarios reduced the inundation level, frequency or duration of 
overbank flows. High river flows expand the extent of wetland and estuarine-margin habitats, 
increase connectivity, deliver nutrients from terrestrial landscapes, create hot spots of high 
primary productivity and food webs, increase prey productivity and availability, and increase 
migration within the river catchment (Burford and Faggotter, 2021; Burford et al., 2016; Leahy and 
Robins, 2021; Ndehedehe et al., 2020, 2021). Reduced flow levels under a future drier climate 
would reduce wetland habitat connectivity and productivity. A wetter climate would likely 
increase wet-season flow levels and increase wetland–riverine–estuarine connectivity, and it could 
ameliorate the effects of possible anthropogenic flow reduction compared with current 
conditions. 

The difference in flow effects of single dams (negligible or minor) or two dams (minor) are 
expected, as the single potential dam on Leichhardt Creek has minimal impact on flow at the 
catchment scale, as it does not affect the majority of subcatchments of the Victoria River. A much 
larger area of the river catchment is located above the dam on the hypothetical Victoria River (B-
DVR). The extent to which the construction of dam infrastructure will reduce barramundi habitat by 
reducing longitudinal connectivity varies depending upon the potential dam location (see Yang et 
al. (2024) for changes associated with instream structures). A potential dam on a small headwater 
catchment such as Leichhardt Creek has minimal impact on longitudinal connectivity of assets 
compared toa a potential dam on the Victoria River. Across the entire catchment, water extraction 
of between 80 and 800 GL (i.e. under scenarios B-W v80t200r30f0 to B-W v800t200r30f0) causes a 
negligible change in flow dependencies for barramundi, including both wet-season high-level flows 
and low-level flows during September to March prior to the wet season. 

Barramundi growth and year-class strength are enhanced by large wet-season flows during the 
wet-season months of January to March (Crook et al., 2022; Leahy and Robins, 2021). Larger flows 
both preceding and following the wet-season peak flows also enhance barramundi growth and 
recruitment. Previous studies have shown that reducing high flows lowers the growth rates of 
barramundi: a model of flow–growth estimates a 12% reduction in barramundi growth under an 
18% reduction in the natural flow regime (Leahy and Robins, 2021). Recent research on monsoon-


driven habitat use by barramundi has shown that, during drier years with lower river flows, a large 
proportion of the juvenile barramundi migrate upstream from estuarine spawning habitat to 
freshwater habitats, probably seeking out riverine and palustrine productive hot spots (Roberts et 
al., 2023). Hence, maintaining low-level flows would be critical. Negligible change in seasonal flow 
levels due to water harvesting maintains the natural seasonality of flow patterns and would 
support barramundi populations within the Victoria River catchment. While two dams within the 
catchment are modelled to result in a minor change to barramundi flows, mitigation actions (such 
as transparent flows) can reduce the level of change to negligible. The impacts on barramundi 
populations from modifying the level and seasonality of flows would be greater under a future dry 
climate and greatest with water resource development under a dry climate, with results similar to 
those modelled in other tropical Australian catchments (Plagányi et al., 2024). 

Shorebirds 

The shorebirds group consists of waterbirds with a high level of dependence on end-of-system 
flows and large inland flood events that provide broad areas of shallow-water and mudflat 
environments (see Stratford et al. (2024a) for a species list). Shorebirds are largely migratory and 
mostly breed in the northern hemisphere (Piersma and Baker, 2000). They are in significant 
decline and are of international concern (Clemens et al., 2010; Clemens et al., 2016; Nebel et al., 
2008). Shorebirds depend on specific shallow-water habitats in distinct geographic areas, including 
northern hemisphere breeding grounds, southern hemisphere non-breeding grounds, and 
stopover sites along migration routes such as the East Asian–Australasian Flyway (Bamford, 1992; 
Hansen et al., 2016). In northern Australia, this group comprises approximately 55 species from 
four families, including sandpipers, godwits, curlews, stints, plovers, dotterels, lapwings and 
pratincoles. Approximately 35 species are common regular visitors or residents. Several species in 
this group are Endangered globally and nationally, including the bar-tailed godwit, curlew 
sandpiper (Calidris ferruginea), eastern curlew, great knot (Calidris tenuirostris), lesser sand plover 
(Charadrius mongolus) and red knot (Calidris canutus). An example species from this group is the 
eastern curlew, which is listed as Critically Endangered and recognised through multiple 
international agreements as requiring habitat protection in Australia. Eastern curlews rely on food 
sources along shorelines, mudflats and rocky inlets, and also need roosting vegetation (Driscoll 
and Ueta, 2002; Finn et al., 2007; Finn and Catterall, 2022). Developments and disturbances, such 
as recreational, residential and industrial use of these habitats, have restricted habitat and food 
availability for the eastern curlew, contributing to population declines. 

The intertidal mudflats and coastal flats provide important habitat for shorebirds, as do the large 
open shallow wetlands (Chatto, 2006). Shorebirds rely on the inundation of shallow flat areas such 
as mudflats and sandflats during seasonal high-level flows to provide invertebrates and other food 
sources. Without inundation events, these habitats cannot support high densities of shorebird 
species, and lack of food can increase mortality rates both on-site and during and after migrations 
(Barbaree et al., 2020; Canham et al., 2021; Durrell, 2000; Kozik et al., 2022; van der Pol, et al., 
2024; West et al., 2005). The analysis considers change in flow regime and related habitat 
changes, and does not consider the addition or loss of potential habitat associated with the 
creation of a dam impoundment (see Yang et al. (2024) for effects of dam impoundments). 










Flow dependencies analysis 
Shorebirds were modelled across a total of 1918 km of assessment reaches in the Victoria 
catchment and in the marine region, with contributing flows from a total of 41 model nodes, using 
eastern curlew as a representative species for understanding distribution patterns (see Stratford 
et al. (2024a)). Some of the key river reaches for shorebirds within the catchment were modelled 
downstream of nodes 81100180, 81100000 and 81100140, based upon species distribution 
modelling. The mean change in important flow dependencies for shorebirds across the Victoria 
catchment for the lowest 30-year, 50-year and 70-year flows in the historical record are 5, 4.5 and 
3.6 respectively. 
Hypothetical water resource development in the Victoria catchment resulted in varying levels of 
change in flow dependencies for shorebirds that did not exceed any of the analogue low-flow 
periods from the historical series (Figure 7-6). The mean change in flow dependencies across all 
41 shorebird analysis reaches and nodes under the hypothetical dam scenarios ranged from 
negligible (0.5) to minor (2.9) under scenarios B-DLCT and BD2, respectively, while under water 
harvesting it was negligible, ranging from 0.2 to 1.5 under scenarios B-Wv80t600t30f500 and 
B-Wv800t200r30f0, respectively (Figure 7-6). Under Scenario Cdry, there was minor change (4.3) for 
shorebirds. The resulting spatial change in flows under the dam and water harvesting, varied due 
to the scale, location and nature of the hypothetical developments. Projected climate scenarios 
resulted in changes to asset flow dependencies across the entire catchment.
Under the hypothetical water harvesting scenarios, there was a mean negligible change in flow 
dependencies across the shorebirds assessment nodes, ranging from 0.2 to 1.5 under scenarios 
B-Wv80t600t30f500 and B-Wv800t200r30f0, respectively. Under the water harvesting scenario with the 
largest change (B--Wv800t200r30f0), the single node with the highest change in flow dependencies was 
81100001, with major (16.2) change. The change in important flow dependencies for shorebirds 
under water harvesting scenarios varies by the extraction targets, pump-start thresholds, pump 
rates, and location (Figure 7-6). With a low extraction target of 80 GL under ScenarioB-Wv80t200r30f0, the mean weighted change across the catchment was negligible (0.4), increasing 
slightly (1.5) with an extraction target of 800 GL under Scenario B-Wv800t200r30f0. Increasing the 
pump-start threshold from 200 ML per day (under Scenario B-Wv160t200r30f0) to 600 ML per day(under Scenario B-Wv160t600r30f0) with a target extraction volume of 160 GL reduced the level of 
change in shorebird flow dependencies across the assessment nodes from 0.6 to 0.4.
Under Scenario Cdry, there were minor mean changes (4.3) for shorebirds across the 41 
shorebirds assessment nodes, with a median value that was equivalent to the analogue low-flow 
time periods (Figure 7-6). This indicates that under the dry climate scenario, there were on 
average across all catchment nodes greater changes than under scenarios B-D2T (negligible; 1.6) 
and B-Wv160t200r30f0 (negligible; 0.6). However, it is important to note that local changes under 
some water resource development scenarios can be greater. Under scenarios Dclim-D2T and 
Ddry-Wv160t200r30, there were moderate (6.4) and minor (4.6) changes in important flows, 
respectively, when weighted across all shorebirds assessment nodes. This shows that the 
combined changes under scenarios Dclim-D2T and Ddry-Wv160t200r30 were greater than under Scenario 
Cdry or either of scenarios B-D2 or B-Wv160t200r30 alone. 
432 | Water resource assessment for the Victoria catchment 




For more information on this figure please contact CSIRO on enquiries@csiro.au






Figure 7-6 Habitat weighted change in important flow dependencies for shorebirds under the various scenarios 
across the model nodes 
Colour intensity represents the level of change occurring in important flow metrics as percentile change from the 
historical conditions weighted by the importance of each reach for shorebirds. Equivalent colour intensity (i.e. 
corresponding to the asset flow dependency change value) for the Ord River below Lake Kununurra shown bottom 
right. Scenarios are ordered on the left axis by the magnitude of change with the mean across nodes shown on the 
right axis. Horizontal grey bars and number correspond to the mean change across all model node locations. Only the 
30 highest impact nodes are shown (x-axis). Results under Scenario A corresponding to changes in asset flow 
dependency for the lowest 30-year, 50-year and 70-year time periods provide a reference for the modelled changes 
under different hypothetical development and projected future climate scenarios. EOS = end-of-system. 
Mangroves 
Mangroves forests include species of shrubs and trees that occupy a highly specialised niche 
within the intertidal and near-supra-littoral zones along tidal creeks, estuaries and coastlines 
(Duke et al., 2019; Friess et al., 2020; Layman, 2007). Mangroves are an important and prolific 
habitat-forming species group in the Victoria River estuary and coastal littoral habitats. Mangrove 
forests provide a complex habitat that offers a home to many marine species, including molluscs 


(McClenachan et al., 2021), crustaceans (Guest et al., 2006; Thimdee et al., 2001), reptiles (Fukuda 
and Cuff, 2013), birds (Mohd-Azlan et al., 2012) and numerous fish species, when connected to 
coastal waters. During periods of inundation at high tide, species including crustaceans access 
mangrove forests, which provide settlement substrates and shelter against predation, using the 
mangroves’ trunks and prop-roots as refugia during postlarval and benthic juvenile phases 
(Meynecke et al., 2010). Fish and crustaceans also access mangroves and their epiphytes for food 
(Layman, 2007; Skilleter et al., 2005). Despite occupying saline habitats, mangroves require 
freshwater inputs from precipitation, groundwater or overbank inundation to thrive (Duke et al., 
2017), so reduced flood flows and an increased frequency and duration of no-flow periods or 
other impacts on hydro-connectivity are key threats to mangroves. 

Flow dependencies analysis 

Mangroves were modelled in the marine region with one model node at the end-of-system. The 
locations for modelling mangroves in the Victoria catchment were based upon habitat maps (see 
Stratford et al. (2024b)). Hypothetical water resource development in the Victoria catchment 
resulted in varying levels of change in important flow dependencies for mangroves. The levels of 
change ranged from negligible (0.8) to moderate (7.4) under hypothetical dam scenarios B-DLCT 
and B-D2, respectively, while the levels of change in important flow dependencies ranged from 
negligible (0.7) to moderate (5.7) under the water harvesting scenarios B-Wv80t600t30f500 and 
B-Wv800t200r30f0, respectively. Under Scenario Cdry, there was moderate change in flows (11.3) formangroves (Figure 7-8). The mean change in important flow dependencies for mangroves acrossthe Victoria catchment for the lowest 30-year, 50-year and 70-year flows in the historical recordare 15.7, 14.3 and 10.1 respectively.



For more information on this figure please contact CSIRO on enquiries@csiro.au
Figure 7-7 Waterhole fringed by boab trees, Victoria catchment 

Photo: CSIRO – Nathan Dyer 




For more information on this figure please contact CSIRO on enquiries@csiro.au






Figure 7-8 Change in important mangroves flow dependencies under the various scenarios 
Colour intensity represents the level of change occurring in important flow metrics as percentile change from the 
historical conditions for mangroves. Equivalent colour intensity (i.e. corresponding to the asset flow dependency 
change value) for the Ord River below Lake Kununurra shown bottom right. Scenarios are ordered on the left axis by 
the magnitude of change with the mean across nodes shown on the right axis. Horizontal grey bars and number 
correspond to the mean change. Results under Scenario A corresponding to changes in asset flow dependency for the 
lowest 30-year, 50-year and 70-year time periods provide a reference for the modelled changes under different 
hypothetical development and projected future climate scenarios. EOS = end-of-system. 
The hydrological requirements for mangroves are complex: they are influenced by tidal 
inundation, rainfall, soil water content, groundwater seepage, and evaporation, all of which 
influence soil salinity, which can have profound effects on mangrove growth and survival. 
Mangroves require access to fresh water via their roots, though many species occur at their upper 
salinity threshold (Robertson and Duke, 1990). Sediment delivered to the coast during flood flows 
helps to sustain mangrove forests, supports their expansion (Asbridge et al., 2016) and increases 
the accumulation of carbon in sediments (Owers et al., 2022). An overall reduction in freshwater 
inputs into mangrove systems could contribute to mangrove stress and potentially dieback, as has 
occurred in the Gulf of Carpentaria (Duke et al., 2019). 
Under scenarios B-DLC and B-DVR flow-modification changes were negligible and moderate 
respectively, and under Scenario B-D2 there were moderate flow-modification changes to 
mangrove flow (Figure 7-8). Water harvesting resulted in moderate negative risks to freshwater 
service provision to mangroves via flow modification during the year. One dam on a small 










headwater tributary had little effect in terms of overall catchment flows, in contrast to a potential 
dam in the mid-reaches of the Victoria River itself, which was associated with a reduction in flow 
volumes compared to the natural flow regime. Incorporating transparent flows in the potential 
dam operations only slightly reduced the change in flow dependency for mangroves. Under 
Scenario B-DVRT, the change in important flow dependency continued to result in a moderate risk 
to the habitat-forming species group. High-level flows are important for inundating the mangrove 
forests during the wet season and replenishing the soil water. Water harvesting would extract 
water during wet-season flows, potentially reducing the magnitude of high flows at the critical 
period of wet-season ecological replenishment in the wet-dry tropics. In addition, reduction of 
sediment loads under flow regime change that results in lower flows would be detrimental due to 
lower levels of coastal deposition to maintain estuarine soils for the benefit of the mangrove 
community (Asbridge et al., 2016). 
Overview of the impacts of water resource development on ecology 
This section provides a high-level overview of the aggregated results (means of assets) arising from 
the hypothetical development and climate change scenarios and discusses specific differences in 
the spatial pattern and magnitude of change. Outcomes for specific assets vary depending upon 
water needs and flow ecology and are discussed with implications and interpretation of results in 
Stratford et al. (2024b). The values associated with the means include, but do not show, the range 
in outcomes across assets, where change in flow dependencies for individual assets or at specific 
locations can be considerably higher or lower than the mean but provide an overview of the 
potential range of outcomes that may occur. 
Hypothetical dams and water harvesting resulted in different changes in flows, affecting outcomes 
for ecology by different magnitudes of change across different parts of the catchment, and in 
different ways (Figure 7-10 and Figure 7-11). Under a water harvesting scenario, Scenario 
B-Wv800t200r30f0 (Figure 7-11), the largest catchment mean changes in flow dependencies for assets 
was for cryptic waders, threadfin, banana prawns and floodplain wetlands, all with moderate 
mean change in flow dependencies across their respective nodes. The largest single-site flow 
change under water harvesting scenarios were major, for assets including for floodplain and 
riparian vegetation, floodplain wetlands, shorebirds and colonial and semi-colonial wading 
waterbirds. Under Scenario B-D2, 89 nodes were rated as having moderate mean change across all 
the assets (out of a total potential of 419 asset nodes representing 21%), compared with 43 (10%) 
under Scenario B-Wv800t200r30f0. Under Scenario B-D2, across all assets there were a total of 16 asset 
nodes (4%) with extreme levels of change in flow dependencies, which was reduced to none under 
Scenario B-Wv800t200r30f0. 
Under Scenario B-D2 with two dams, the largest catchment mean change in flow dependencies for 
assets were for threadfin, cryptic wading waterbirds, banana prawns and mangroves, each with 
moderate mean change in flow dependencies across all their assessment nodes. Considering the 
mean of all assets, the change in flow dependencies under the largest water resource 
development scenario modelled (B-D2) was lower than that for all three of the benchmark low-
flow time periods (Figure 7-11), although individual assets may have differing outcomes (see 
Stratford et al. (2024b)). Under scenarios with dams, the largest site-based changes in flow for 
assets were often directly downstream of hypothetical dams and resulted in node impacts with up 
to extreme change for assets, including floodplain wetlands, colonial and semi-colonial wading 
436 | Water resource assessment for the Victoria catchment 






waterbirds, grunter and sawfish at these impacted downstream nodes (e.g. Figure 7-11d for 
downstream dam impacts). 
Under Scenario Cdry, flow regime change impacts on ecology occurred largely across the 
catchment (Figure 7-10e), and cumulative impacts of water resource development in combination 
with dry future climate often led to the greatest catchment-level changes in flow ecology (Figure 
7-10f showing D-dryw160t200r30 and Figure 7-11).
Under the largest hypothetical development scenarios for water harvesting (e.g. B-Wv800t200r30f0) 
and instream dam (Scenario B-D2) developments, the impacts at the end-of-system node alone 
were greater under water harvesting than dams for sawfish, shorebirds and salt flats, and 
inversely greater under dams for mullet, threadfin, barramundi and mangroves. The flow changes 
under scenarios with a single dam ranged from negligible to moderate at the end-of-system for 
the mean across assets (negligible under Scenario B-DLC and minor to moderate under Scenario 
B-DVR). While some assets have extreme change at some nodes downstream of dams, as 
unimpacted tributary inflows increasingly dominate streamflow patterns with distance 
downstream from the dam the impact is reduced. 



For more information on this figure please contact CSIRO on enquiries@csiro.au
Figure 7-9 Riverine landscape, Victoria catchment 

Photo: CSIRO – Nathan Dyer 




For more information on this figure please contact CSIRO on enquiries@csiro.au
Figure 7-10 Spatial heatmap of change to asset–flow dependencies across the Victoria catchment, considering 
change across all assets in the locations in which each of the assets was assessed 

Scenarios are: (a) B-Wv80t200r30f0, (b) B-Wv160t200r30f0, (c) B-W160t60r20f0, (d) B-DLC, (e) Cdry and (f) D-dryw160t200r30. See 
Table 7-1 for descriptions of scenarios. River shading indicates the mean level of flow change of important metrics 
weighted by the habitat value of each asset for each reach. 




For more information on this figure please contact CSIRO on enquiries@csiro.au
Figure 7-11 Mean change to assets’ important flow dependencies across scenarios and nodes 

The scenarios (see Table 7-1) are listed on the left vertical axis. The x-axis lists river system model nodes (i.e. 
locations). Colour intensity represents the mean level of change occurring in the assets’ important flow metrics under 
the various scenarios, given the habitat importance of each node for each asset. See Table 7-1 for descriptions of the 
scenarios and Figure 7-2 for a map of the gauge locations. Heatmap shading indicates the mean level of flow change of 
important metrics, weighted by the habitat value of each asset for each reach. EOS = end-of-system. Horizontal grey 
bars and number correspond to the mean change across all model node locations. 




Water harvesting and mitigation of impacts 

For water harvesting scenarios, measures to mitigate the risks of extraction include limiting the 
system target thereby reducing extraction across the catchment, providing a pump-start threshold 
by limiting pumping of water from the river during periods of low river flows, providing an end-of-
system requirement for a volume of water to pass the last node in the river system before 
pumping is allowed to commence that water year, and limiting the pump rate that water can be 
extracted from the river (see Hughes et al. (2024b) simulation report for more details). 

Providing reduced limits on system targets improves outcomes for ecological flow dependencies 
compared with larger targets (Figure 7-12 y-axis); this applies broadly across all asset groups and 
throughout the range of explored irrigation targets. Larger extraction volumes resulted in 
increases in mean changes in flow dependencies across asset groups up to moderate change 
across the catchment’s ecological assets. Some assets, including flow-dependent habitats, the 
‘other’ species group and marine assets experienced higher changes in important flow 
dependencies at some system targets (Figure 7-12). While improvements are likely to occur in 
conjunction with providing either minimum flow thresholds or end-of-system requirements, 
greater extraction equates to a greater level of risk due to changes in important ecological flow 
metrics. 

Providing minimum flow pump-start thresholds improved ecological flow dependencies across 
increasing pump-start threshold levels (Figure 7-12 x-axis). Modelled minimum flow thresholds 
varied incrementally from 200 to over 1000 ML/day and are provided by requiring that flow 
volume in the river exceeds required thresholds before pumping commences. Increasing pump-
start threshold to 1000 ML/day results in a significant reduction in modelled mean change in 
important flow dependencies compared with only 200 ML/day (Figure 7-12). Increasing the pump-
start threshold above 600 ML/day results in incremental improvements to ecological flows with 
reduced rate of relative improvement to levels of change in important flow dependencies above 
about 900 ML/day (Figure 7-12). The benefit of higher pump-start thresholds was largest in 
scenarios with no or low EOS requirements, as the benefit of having higher pump-start thresholds 
was reduced in combination with scenarios that had greater EOS requirements. This is likely 
because large flows have already passed the system to the EOS node before the pump-start 
threshold is triggered. 




For more information on this figure please contact CSIRO on enquiries@csiro.au
Figure 7-12 Mean change to assets’ important flow dependencies across water harvesting increments of system 
target and pump-start threshold, with no end-of-system (EOS) requirement and a pump rate of 30 days 

Colour intensity represents the mean level of change occurring in the assets’ important flow metrics under the various 
scenarios, given the habitat importance of each node for each asset. 




Instream dams with and without transparent flows 

Two hypothetical locations for instream dams were selected (Leichhardt Creek and Victoria River) 
for modelling and analysis (Yang et al., 2024) and simulated following the hydrology modelling 
approach outlined in Hughes et al. (2024b). The locations are shown in Figure 7-2. The goal of this 
analysis was to test the effect of different dam locations and configurations on changes to 
streamflow, to understand the effect on downstream ecology. These hypothetical dams were 
modelled individually, as well as two dams together, to better understand cumulative impacts. In 
addition, the hypothetical dams were also modelled incorporating transparent flows. Instream 
dams create a range of impacts on streamflow associated with the capture and extraction of 
water, affecting the timing and magnitude of downstream flows. The risks on downstream flow 
associated with instream dams are explored here across broad asset groups, and the results are 
presented as the mean of asset values. Impacts associated with loss of connectivity due to the 
dam wall and loss of habitat associated with the dam inundation extent are discussed in Yang et al. 
(2024. The dam scenarios and the resulting flow–ecology relationships are discussed in more 
detail for each asset in Stratford et al. (2024b). 

Assessment of the individual dams found varying levels of impact on ecology–flow dependencies 
(Table 7-4). None of the scenarios resulted in changes greater than minor averaged for all assets 
across the catchment, although local impacts were often considerably higher. The dams varied in 
size, inflows, and capture volumes, and the location within the catchment, all of which influenced 
the outcome. Impacts directly downstream of modelled dams can often be high and may cause 
extreme changes in ecology–flow dependencies. Areas further downstream have contributions 
from unimpacted tributaries that help support natural flow regimes. Dams further up the 
catchment may affect a larger proportion of streams and river reaches when considering flow 
regime change, but they may have lower impacts associated with connectivity. Impacts are not 
equivalent across assets, and large local impacts may lead to changes in ecology across other parts 
of the catchment due to the connected nature of ecological systems. 

Table 7-4 Scenarios of different hypothetical instream dam locations showing end-of-system (EOS) flow and mean 
changes in ecology flows for groups of assets across each asset’s respective catchment assessment nodes 

Higher values represent greater change in flows important to the assets of each group. Values are asset means across 
their respective catchment assessment nodes (see Stratford et al. (2024b)). Some assets are considered in multiple 
groups, in which cases the mean across the nodes is used. Asset means include values from all nodes that the asset is 
assessed in, including in reaches that may not be affected by flow regime change. 

SCENARIO 

HYPOTHETICAL DAM 
SCENARIO DESCRIPTION 

ALL-ASSET 
MEAN 

FISH 

WATERBIRDS 

OTHER 
SPECIES 

HABITATS 

FRESHWATER 
ASSETS 

MARINE 
ASSETS 

B-DLC 

Leichhardt Creek 

1.1 

1.0 

1.0 

0.9 

1.2 

1.2 

0.9 

B-DLCT 

Leichhardt Creek with 
transparent flows 

0.6 

0.4 

0.6 

0.6 

0.8 

0.5 

0.7 

B-DVR 

Victoria River 

3.6 

3.2 

3.1 

4.3 

4.0 

2.5 

4.5 

B-DVRT 

Victoria River with 
transparent flows 

2.6 

1.9 

1.9 

3.3 

3.5 

1.4 

3.7 

B-D2 

Both Leichhardt Creek 
and Victoria River dams 

4.5 

4.1 

4.1 

4.9 

5.1 

3.7 

5.2 

B-D2T 

Both Leichhardt Creek 
and Victoria River dams 
with transparent flows 

2.7 

2.0 

2.2 

3.1 

3.9 

1.8 

3.6 




The cumulative change in flow dependencies due to multiple dams (Scenario B-D2) is greater than 
the change in flow dependencies due to individual dams, considering both change in flow volumes 
and ecology–flow dependencies (Table 7-4). Cumulative change in flow ecology may be associated 
with the combination of a larger portion of the catchment being affected by changes in flows 
across larger parts of the catchment, and residual flows being lower due to the overall greater 
level of abstraction (Table 7-4). 

Measures to mitigate the risks of large instream dams, such as transparent flows resulted in 
reduced ecological change in flows broadly across all assets compared with no transparent flows 
(Table 7-4). Particularly strong benefits from transparent flows were found for fish (Table 7-4). 
Instream dams capture inflows and change downstream flow regimes. Transparent flows are a 
type of environmental flow provided as releases from dams that maintain some aspects of natural 
flows. Inflow thresholds used in the transparent flows analysis are conceptually similar to the 
commence-to-pump thresholds used in water harvesting, facilitating comparison. Transparent 
flows are provided across both dams under Scenario B-D2 (Hughes et al., 2024b). 

7.4 Biosecurity considerations 

7.4.1 Introduction 

Biosecurity is the prevention and management of pests, weeds and diseases, both terrestrial and 
aquatic, to limit the risk of detrimental economic, environmental, social and/or cultural impacts. 
‘Pests’ is a broad term encompassing pest insects, other invertebrates (e.g. nematodes, mites, 
molluscs) and vertebrates (e.g. mammals, birds, fish). Weeds broadly include invasive plants and 
algae. Diseases are caused by pathogens or parasites such as bacteria, fungi and viruses. 

Any development of the water resources within the Victoria catchment for plant industries or 
aquaculture must take account of biosecurity risks that may threaten production or markets. 
Development in the region may also pose broader biosecurity risks to other industries, the 
environment or communities, and these risks must be prevented and/or managed. 

Biosecurity practices to protect the Victoria catchment occur at a range of scales. At the national 
level, the Australian Government imposes quarantine measures to regulate the biosecurity risks 
associated with entry of goods, materials, plants, animals and people into Australia. The NT 
Government also has biosecurity legislation to limit the entry of new pests, weeds and diseases 
into the jurisdiction, and to require the control of certain species already established within the 
NT. There can also be requirements at the regional level, such as participating in weed 
management programs (NT Government, 2021). At the local scale, individual properties ideally 
follow routine biosecurity protocols, and work with other similar enterprises in implementing 
industry-wide biosecurity measures. 

While the Victoria catchment is relatively isolated compared with other regions of Australia, it still 
has physical connections to the rest of the NT, across northern Australia more broadly, with the 
rest of the country and with neighbouring countries such as Indonesia. Examples of such 
connections are the sharing of specialist cropping machinery between agricultural regions, 
transport of crop products, tourist visits into remote areas, international trade and tourism, 


mining exploration, shifting cattle between pastoral properties, army training exercises and 
movements between Indigenous communities. These connections can be pathways for entry of 
new pests, weeds or diseases. 

This section introduces the impacts, spread and management of pests, weeds and diseases of 
irrigated cropping and aquaculture, as well as invasive species that pose a risk to the Victoria 
catchment. Given the focus on water-intensive primary industries, biosecurity for terrestrial 
livestock industries is not included. 

Impacts of pests, weeds and diseases 

In primary industries, pests, weeds and diseases can cause economic losses by reducing crop yield 
and product quality, interfering with farm operations and loss of market access, plus the costs of 
control measures. The national economic impact of established weeds and vertebrate pests on 
Australian agriculture has been estimated at over $5.3 billion/year (Hafi et al., 2023). Insect pests 
are also a substantial economic burden nationally (Bradshaw et al., 2021). 

The environmental impacts of pests, weeds and diseases, collectively termed ‘invasive species’, 
include loss of native plants and animals (from competition, predation and infection), degradation 
of habitats and disruption of ecosystem processes (e.g. changed fire or moisture regimes). Invasive 
species are the greatest threat to Australia’s threatened flora and fauna (Ward et al., 2021). For 
example, myrtle rust (Austropuccinia psidii) has potential to cause the extinction of some rare, 
native myrtaceous shrubs and trees (Makinson et al., 2020). 

Social impacts of pests, weeds and diseases include loss of public amenity and access to outdoor 
areas, damage to infrastructure and public safety risks. Cultural impacts include a loss of 
traditional foods, impaired access for hunting and damage to cultural sites. For example, Gamba 
grass (Andropogon gayanus) is an African grass originally introduced for pasture in the NT that is 
now a Weed of National Significance (WoNS). WoNS are nationally agreed weed priorities that 
have been a focus for prevention and improved management (CISS, 2021; Hennecke, 2012). 
Gamba grass forms tall, dense stands that burn intensely, posing significant risks to public safety, 
community and primary industries infrastructure, Indigenous heritage sites, native ecosystems and 
grazing lands (Setterfield et al., 2013). 

Pathways of movement 

Pests, weeds and diseases spread by movement of adults and juveniles (e.g. vertebrate pests), 
with movement of their hosts (e.g. infected aquaculture broodstock or nursery stock for planting, 
harvested produce infested with insect larvae) and by movement of propagules (e.g. fungal 
spores, insect eggs, weed seeds, viral particles). Such movements provide many pathways by 
which pests, weeds and diseases could be introduced to the Victoria catchment, potentially 
causing new outbreaks. Just as importantly, there is also the potential for pests, weeds and 
diseases from the Victoria catchment to spread to other areas in the NT and elsewhere in 
Australia. 

Human-mediated spread 

Human activities are the key means of long-distance and local movement. Pests and propagules, 
including those within transported soil, can ‘hitchhike’ on or in vehicles, construction and farm 
machinery, shipping containers and other equipment brought into a region. The ease of 


movement on vehicles and machinery means that the road network (including access roads to 
camping areas, railways, pipelines and powerlines) can be a frequent source of new infestations. 

Propagules may contaminate livestock, seed or nursery stock for establishing crops, hay, road base 
and landscaping supplies (including turf and ornamental plants). Weed infestations can also arise 
from invasive garden, crop and pasture plants. Aquatic pests and diseases may become 
established due to deliberate species release into the environment for fishing, inadvertent 
transport on fishing equipment or vessels, or dumping of aquarium contents. 

Incursions of new pests, weeds and diseases from overseas are most likely to occur through 
contamination of imported goods or containers, or be carried by people (e.g. propagules on shoes 
or clothing, smuggling of seed or fruit). 

Natural spread 

Natural dispersal via wind, water and wild animals usually occurs over short distances. Extreme 
weather events such as floods and cyclones can disperse pests, weeds and diseases over long 
distances in addition to causing major environmental disturbances that increase the likelihood of 
invasive species becoming established. Irrigation infrastructure such as dams, pipelines and 
channels may facilitate distant spread via water movements of some pests, weeds and diseases, 
within and across catchments. Some animal pests, such as locusts and fall armyworm (Spodoptera 
frugiperda) naturally migrate long distances. 

Northern Australia is close to the southern coasts of Indonesia, Timor-Leste and Papua New 
Guinea (PNG). These neighbouring countries have a range of serious plant pests and diseases that 
are not present in Australia, including exotic fruit flies and citrus canker (Xanthomonas citri subsp. 
citri). The likelihood of their arrival by long-distance wind dispersal is uncertain, particularly with 
regards to novel atmospheric conditions and extreme weather events occurring under climate 
change. However, their economic consequences in Australia would be severe were they to 
establish in Australia. Thus, ongoing biosecurity vigilance in northern Australia through 
government, industry and community surveillance is vital (DAFF, 2024a; PHA, 2021). 

7.4.2 Pest, weed and disease threats to the Victoria catchment 

The Victoria catchment principally faces biosecurity risks from pests, weeds and diseases already 
present in the catchment, and those that occur in neighbouring regions of northern Australia. 
However, pests, weeds and diseases could also come from other parts of Australia with similar 
climates and/or production systems, or from overseas. 

Examples of pests, weeds and diseases that pose a risk to the Victoria catchment are highlighted in 
the following sections. Whether any one of these would have a significant impact at the property 
level depends on the local environment, land use and agricultural or aquatic enterprise. However, 
there is a legal requirement to prevent and manage any pests, weeds or diseases that are formally 
‘declared’ under the NT’s biosecurity legislation, regardless of its local impact. 


Plant industries 

The priority pests and diseases for cropping in the Victoria catchment depends on what is grown. 

Table 7-5 includes some examples of high-impact pest and diseases threats to particular crops, 
and their current status. The NT Government website provides local plant pest and disease 
management information (NT Government, 2024a), while the NT Plant Health Manual lists all 
declared pests and diseases (NT Government, 2023). Plant Health Australia is a centralised 
resource on exotic (i.e. overseas) biosecurity risks to Australia’s plant industries. Research and 
development corporations, including the Grains Research and Development Corporation, the 
Cotton Research and Development Corporation, AgriFutures Australia and Hort Innovation also 
provide extension publications on identifying and managing biosecurity threats. 

Many pests and diseases have a high host specificity to a particular crop, but there are also 
generalists that can use many crops as hosts. Local native species can also pose risks of impacts. 
For example, naturally occurring pathogens of certain native wild rices may infect cultivated rice 
(Chapman et al., 2020) or native animals may graze on crops. 

Irrigation brings the potential for year-round cropping, which can provide a ‘green bridge’ in the 
dry season to enable pests or diseases, including native insects and diseases, to persist and 
increase locally, and to potentially spread to other areas. 

A significant new generalist pest of cropping is fall armyworm, which has become widely 
established across northern Australia since a national incursion was detected in 2020. It is likely to 
be present year round in the Victoria catchment, with a lower incidence in the dry season (PHA, 
2020). Fall armyworm caterpillars favour C4 grass crops (e.g. maize, sorghum, rice) and pastures 
but may also feed on broadleaved crops such as soybean, melon, green bean and cotton. Young 
crops are most at risk of severe damage and can require immediate insecticide treatment if 
invaded at levels above the damage threshold. 

Cucumber green mottle mosaic virus (CGMMV) infects a wide range of cucurbit crops, including 
various melons, cucumber, pumpkin and squash, and can also be hosted by a range of 
broadleaved crop weeds. It causes plant stunting and fruit discolouration, malformation and 
rotting. CGMMV is present on a number of farms in the NT and has also been found interstate. Its 
presence on-farm can make access to interstate markets more difficult as many jurisdictions have 
imposed quarantine requirements. Infected plants cannot be treated, so preventive farm 
biosecurity measures are vital (NT Government, 2024a). 

Types of weed threats differ between plant industries according to production methods. For 
example, annual grain and cotton crops tend to have annual weeds (grasses and herbs) and 
herbaceous perennials that persist and spread vegetatively through underground rhizomes. 
Perennial horticulture disturbs the soil less, so typically has more perennial grasses and perennial 
broadleaved weeds. The highest priority weeds tend to be those that are most difficult to control, 
such as herbicide-resistant biotypes or species that are otherwise tolerant to routinely used 
herbicides. For example, some annual grasses that invade cotton crops have developed resistance 
to certain herbicides, including barnyard grass (Echinochloa spp.) and feathertop Rhodes grass 
(Chloris virgata) (CRDC, 2023). 

Various native vertebrates may consume grain and horticultural crops that are becoming 
established and damage tree crops. These vertebrate pests, include birds (waterfowl, cockatoos), 


macropods (kangaroos, wallabies) and rodents. Large flocks of magpie geese (Anseranas 
semipalmata) can be particularly destructive, by trampling, grazing, uprooting and consuming fruit 
(Clancy, 2020). 

Table 7-5 Examples of significant pest and disease threats to plant industries in the Victoria catchment 

BIOSECURITY THREAT 

CURRENT STATUS 

CROPS AT RISK 

FURTHER INFORMATION 

INVERTEBRATE PESTS 

Asian citrus psyllid 
Diaphorina citri 

Incursion risk from overseas 
(including Indonesia and 
PNG). 

citrus 

www.agriculture.gov.au/biosecurity-
trade/policy/australia/naqs/naqs-target-
lists/pests_of_plants_asian_citrus_psyllid 

cluster caterpillar 
Spodoptera litura 

Widespread in northern 
Australia. 

cotton, pulses, 
brassicas 

www.business.qld.gov.au/industries/farms-fishing-
forestry/agriculture/biosecurity/plants/insects/field-
crop/cluster-caterpillar 

fall armyworm 
Spodoptera frugiperda 

Established across northern 
Australia, following first 
detection in 2020. 

grasses (cereal 
and fodder), 
cotton, soybean, 
melon, green 
beans 

www.nt.gov.au/industry/agriculture/food-crops-
plants-and-quarantine/fall-armyworm 



fruit flies, various species 
including: 

Mediterranean fruit fly 
Ceratitis capitata 

melon fruit fly 
Zeugodacus cucurbitae 

oriental fruit fly 
Bactrocera dorsalis 

New Guinea fruit fly 
B.trivialis

Queensland fruit flyB.tryoni

Mediterranean fruit fly 
established in WA. 
Queensland fruit fly endemic 
in NT. Melon, oriental, New 
Guinea and other exotic fruit 
fly incursion risks from 
overseas (including Indonesia, 
PNG) and the Torres Strait. 
Various species declared. 

fruit and fruiting 
vegetable crops 

www.agriculture.gov.au/biosecurity-trade/pests-
diseases-weeds/fruit-flies-australia 

www.agriculture.gov.au/biosecurity-
trade/policy/australia/naqs/naqs-target-lists/fruit-
flies 

Bollworms 
Helicoverpa spp. 
Pectinophora spp. 

Widespread in northern 
Australia. 

cotton, pulses, 
brassica, 
sunflower, 
sorghum, maize 

www.crdc.com.au/publications/cotton-pest-
management-guide 

guava root-knot 
nematode 
Meloidogyne enterolobii 

Recent detection in Darwin 
region. Declared. 

cucurbits, 
solanaceous 
crops, sweet 
potato, cotton, 
guava, ginger 

www.nt.gov.au/industry/agriculture/food-crops-
plants-and-quarantine/guava-root-knot-nematode 

Leafminers 

American serpentine 
leafminer 
Liriomyza trifolii 

serpentine leafminer 
L.huidobrensis

vegetable leafminerL.sativae 

Serpentine and American 
serpentine leafminers are 
recent incursions now present 
in various locations across 
Australia. Vegetable leafminer 
an incursion risk from 
overseas and Torres Strait and 
is declared in NT. 

vegetables, 
cotton 

www.business.qld.gov.au/industries/farms-fishing-
forestry/agriculture/biosecurity/plants/priority-
pest-disease/serpentine-leafminer 

www.agriculture.gov.au/biosecurity-
trade/policy/australia/naqs/naqs-target-
lists/vegetable_leaf_miner 

mango pulp weevil 
Sternochetus frigidus 

Incursion risk from overseas 
(including Indonesia). 
Declared. 

mango 

www.agriculture.gov.au/biosecurity-
trade/policy/australia/naqs/naqs-target-
lists/mango-pulp-weevil 

mango shoot looper 
Perixera illepidaria 

Recent incursion in 
Queensland and NT. Not 
declared. 

mango, lychee 

www.nt.gov.au/industry/agriculture/food-crops-
plants-and-quarantine/mango-shoot-looper 

melon thrips 
Thrips palmi 

Limited presence in NT north 
of Alligator township. 

vegetables 

www.nt.gov.au/industry/agriculture/food-crops-
plants-and-quarantine/plants-and-
quarantine/travelling-within-the-nt 




BIOSECURITY THREAT 

CURRENT STATUS 

CROPS AT RISK 

FURTHER INFORMATION 

spur-throated locust 
Austracris guttulosa 

Native to northern Australia. 

grasses (cereal 
and fodder), 
sunflowers, 
soybeans, cotton 

www.agriculture.gov.au/biosecurity-trade/pests-
diseases-weeds/locusts/about/spur-throated 

DISEASES 

Alternaria leaf blight 
Alternaria alternata 

Present in northern Australia. 

cotton 

www.crdc.com.au/publications/cotton-pest-
management-guide 

banana freckle 
Phyllosticta cavendishii 

Under eradication in NT. 
Declared. 

banana 

www.nt.gov.au/industry/agriculture/food-crops-
plants-and-quarantine/banana-freckle 

brown spot 
Cochliobolus miyabeanus 

Endemic on wild rices in 
northern Australia. 

rice 

www.agrifutures.com.au/product/rice-growing-
guide-north-queensland 

citrus canker 
Xanthomonas citri subsp. 
citri 

Eradicated from NT and 
Queensland. Incursion risk 
from overseas (including 
Indonesia, Timor-Leste and 
PNG). Declared. 

citrus 

www.nt.gov.au/industry/agriculture/food-crops-
plants-and-quarantine/citrus-canker 

cucumber green mottle 
mosaic virus 

Present in certain areas in NT 
and other states. 

cucurbits 

www.nt.gov.au/industry/agriculture/food-crops-
plants-and-quarantine/cucumber-green-mottle-
mosaic-virus 

Fusarium wilt 
Fusarium oxysporum f. 
sp. vasinfectum 

Not present in NT. Declared. 

cotton 

www.crdc.com.au/publications/cotton-pest-
management-guide 

Huanglongbing 
Candidatus Liberibacter 
asiaticus 

Incursion risk from overseas 
(including Indonesia, Timor-
Leste and PNG). Declared. 

citrus 

www.agriculture.gov.au/biosecurity-trade/pests-
diseases-weeds/plant/huanglongbing 

Panama TR4 
Fusarium oxysporum f. 
sp. cubense 

Established throughout NT. 
Declared. 

banana 

www.business.qld.gov.au/industries/farms-fishing-
forestry/agriculture/biosecurity/plants/priority-
pest-disease/panama-disease 

rice blast 
Pyricularia oryzae 

Endemic on wild rices in 
northern Australia. 

rice 

www.dpi.nsw.gov.au/biosecurity/plant/insect-pests-
and-plant-diseases/rice-blast 



Declaration status is under the Plant Health Act 2008 (NT), derived from NT Government (2023). Links to further information are current as of 
March 2024. PNG = Papua New Guinea. 

Aquaculture 

A wide range of diseases and parasites are of concern to Australian aquaculture (DAWE, 2020a), 
including those not known to be in Australia, those now established (i.e. endemic) in Australia and 
those native to Australian ecosystems. 

Barramundi farmers need to consider preventing and managing the biosecurity risks of a range of 
endemic parasites and viral, bacterial and fungal pathogens that naturally occur in northern 
Australia (Irvin et al., 2018). In addition, national quarantine measures are vital to prevent exotic 
disease risks for barramundi from entering Australia (Landos et al., 2019). 

Prawn aquaculture in northern Australia is most at risk from white spot syndrome virus (WSSV), 
for which there have been national incursion responses at prawn farms and hatcheries in south-
east Queensland and northern NSW. However, there are also many other exotic crustacean 
diseases (DAWE, 2020a). Endemic viruses (and endemic genotypes of viruses also found overseas) 
that occur naturally in Australian waters can also trigger mortalities or reduce productivity (Irvin et 
al., 2018). 


Invasive species 

Invasive species, whether pest, weed or disease, are commonly characterised as occurring across 
multiple land uses in a landscape. Their impacts will vary between land uses, but their coordinated 
control requires action across all tenures. 

Weeds 

Table 7-6 lists regional weed priorities in the Victoria catchment (NT Government, 2021). All of 
these weeds are currently declared under the Northern Territory Weed Management Act 2001, 
other than other than coffee bush (Leucaena leucocephala), giant rat’s tail grass (Sporobolus spp.) 
and yellow oleander (Cascabela thevetia). Many in Table 7-6 are WoNS. These are nationally 
agreed weed priorities that have been a focus for prevention and improved management (CISS, 
2021; Hennecke, 2012). For example, the parthenium weed (Parthenium hysterophorus), one of 
the WoNS, is a direct competitor to and contaminant in dryland and irrigated crops, and poses a 
health risk to animals and people as a severe allergen. 

Aquatic weeds can hamper the efficient function of irrigation infrastructure and cause severe 
ecological impacts through dense infestations in waterways and wetlands. More-constant water 
flows from within-stream reservoirs can change riparian conditions from seasonally ephemeral to 
perennial, predisposing native vegetation to invasion by weeds that thrive in moist environments. 

Terrestrial vertebrate pests 

Various large feral herbivores are present in the Victoria catchment, including feral buffalo 
(Bubalus bubalis), horses (Equus caballus), donkeys (E. asinus), pigs (Sus scrofa) and camels 
(Camelus dromedarius). They can directly affect agricultural production through grazing impacts, 
severe soil erosion and damaged infrastructure such as fencing and irrigation channels. Feral 
animal damage to habitats is a key disturbance mechanism that facilitates weed invasion, 
particularly in riparian and wetland areas. Feral pigs in particular are a major threat to irrigated 
cropping. Their daily water requirement means that they concentrate during the dry season 
around watercourses and man-made water supplies (Bengsen et al., 2014). 

Cane toads (Rhinella marina) are already established in the Victoria catchment (Kearney et al., 
2008), but would likely become more abundant around irrigation developments, where they could 
access year-round moisture. 

Aquatic pests 

Freshwater aquatic pests such as non-native fish, molluscs and crustaceans can affect biodiversity 
and ecosystem function. While these pests may not directly affect irrigated cropping, the 
associated infrastructure (e.g. dams, channels, drains) brings increased risk of deliberate release 
by people for recreational fishing or in the disposal of aquarium contents. This infrastructure can 
also provide enhanced habitat and pathways for the persistence and dispersal of aquatic pests and 
weeds in the catchment (Ebner et al., 2020). 


Table 7-6 Regional weed priorities and their management actions in the Victoria catchment 

Source: NT Government, 2021; NT Government officers, pers. comm. 

LIFEFORM AND WEED 

REGIONAL ACTION 

HABITATS AT RISK: 

AQUATIC 
(e.g. river, 
wetland, dam) 

WETTER AREAS 
(e.g. riparian, 
floodplain, drain) 

DRIER AREAS 
(e.g. grassland, 
woodland) 

AQUATIC/SEMI-AQUATIC HERB 

cabomba Cabomba caroliniana† 

P 

✓

✓



limnocharis Limnocharis flava 

P 

✓

✓



sagittaria Sagittaria platyphylla† 

P 

✓

✓



salvinia Salvinia molesta† 

P 

✓

✓



water hyacinth Pontederia crassipes† 

P 

✓

✓



water mimosa Neptunia plena 

P 

✓

✓



GRASS 

buffel grass Cenchrus ciliaris, C. pennisetiformis 

§ 





✓

gamba grass Andropogon gayanus†‡ 

E 



✓

✓

giant rat’s tail grass Sporobolus spp. 

P 





✓

grader grass Themeda quadrivalvis‡ 

C 





✓

hymenachne Hymenachne amplexicaulis† 

P 

✓





thatch grass Hyparrhenia rufa 

P 





✓

BROADLEAVED HERB 

devil’s claw Martynia annua 

E 





✓

Parthenium weed Parthenium hysterophorus† 

P 



✓

✓

CLIMBER/VINE 

rubber vine Cryptostegia grandiflora† 

P 



✓

✓

ornamental rubber vine C. madagascariensis 

P 



✓

✓

TREE/SHRUB 

Athel pine Tamarix aphylla†‡ 

E 



✓



bellyache bush Jatropha gossypiifolia†‡ 

C 





✓

calotrope Calotropis procera, C. gigantea 

M 





✓

Chinese apple Ziziphus mauritiana‡ 

C 



✓

✓

coffee bush Leucaena leucocephala 

M 



✓



lantana Lantana camara† 

P 







mesquite Prosopis spp.†‡ 

E 



✓

✓

mimosa Mimosa pigra†‡ 

E 

✓





neem Azadirachta indica‡ 

C 



✓



parkinsonia Parkinsonia aculeata† 

M 



✓



pond apple Annona glabra† 

P 

✓

✓



prickly acacia Vachellia nilotica†‡ 

E 





✓

Siam weed Chromolaena odorata 

P 



✓

✓

yellow oleander Cascabela thevetia 

M 



✓

✓

OTHER 

rope cactus Cylindropuntia spp.† 

P 





✓



† On the Weeds of National Significance (WoNS) list. 

‡ Have statutory management plans under the Weeds Management Act 2001 (NT). 

§ Declared in 2024 and thus not categorised for management action in the current regional weed management plan (NT Government, 2021). 

C = strategic control target (control and containment of core infestations, eradication of outlier populations, prevention elsewhere). 

E = eradication target (few infestations known). 

M = widely established; regional management focused on protecting assets at risk. 

P = alert weed for prevention and early intervention. 


Table 7-7 includes examples of high-risk pest fish for the Victoria catchment. Certain species are 
formally declared as noxious under the Northern Territory Fisheries Regulations 1992. However, 
those not declared noxious are still covered by a general precautionary provision that excludes 
import into the NT and possession of non-native fish that are not on the Australian Government’s 
list of permitted live freshwater ornamental fish (DAFF, 2023), or otherwise not listed as a 
permitted import in Schedule 7 of the Regulations. 

Table 7-7 High-risk freshwater pest fish threats to the Victoria catchment 

Source: Australian Government and NT Government, n.d.; Queensland Government, 2023 

PEST FISH 

LEGAL STATUS 
(IF ANY) 

CURRENT DISTRIBUTION 

alligator gar Atractosteus spatula 

N 

Not known to be in the wild in Australia. 

black pacu Piaractus brachypomus 

E 

Not known to be in the wild in Australia. Risk of incursion 
from PNG. 

carp Cyprinus carpio 

N 

Not known to be in the wild in NT. 

cichlids, including tilapia: 

giant cichlid Boulengerochromis microlepis 



N 

Giant cichlid not known to be in the wild in Australia. 

Jaguar, pearl and Texas cichlid and Mozambique and 
spotted tilapia present in the wild in Queensland. 

Mozambique tilapia and pearl cichlid also present in the 
wild in WA. Not known to be in the wild in NT. 

Nile tilapia an incursion risk from northern Torres Strait. All 
tilapia species noxious. 

jaguar cichlid Parachromis managuensis 

E 

Mozambique tilapia Oreochromis mossambicus 

N 

Nile tilapia O. niloticus 

N 

pearl cichlid Geophagus brasiliensis 

E 

spotted tilapia Pelmatolapia mariae 

N 

Texas cichlid Herichthys cyanoguttatus 

E 

climbing perch Anabas testudineus 

N 

Risk of incursion from northern Torres Strait. 

gambusia / mosquito fish Gambusia holbrooki 

N 

Not known to be established in NT (eradicated in Darwin 
and Alice Springs). Recorded in the wild across Queensland 
and parts of WA. 

guppy Poecilia reticulata 



Recorded in Darwin and Nhulunbuy in NT. Likely to be 
present elsewhere. 

marbled lungfish Protopterus aethiopicus 

N 

Not known to be in the wild in Australia. 

oriental weatherloach Misgurnus anguillicaudatus 

N 

Not known to be in the wild in NT. 

oscar Astronotus ocellatus 



Not known to be in the wild in NT. Present in the wild in 
Queensland. 

platy Xiphophorus maculatus 



Present in the wild in Darwin and Nhulunbuy in NT, and in 
eastern Queensland. 

Siamese fighting fish Betta splendens 



Established in the Adelaide catchment in NT. Not known to 
be in the wild elsewhere in Australia. 

spotted gar Lepisosteus oculatus 

N 

Not known to be in the wild in Australia. 

swordtail Xiphophorus hellerii 



Present in the wild in Darwin and Nhulunbuy in NT, and in 
eastern Queensland. 



E = excluded for imports into and possession in the NT. 
N = noxious under the Northern Territory Fisheries Regulations 1992. 
n.d. = no date.




Terrestrial invertebrates 

Terrestrial invertebrates can be high-impact invasive species. For example, certain exotic ants 
form ‘super colonies’ from which they outcompete native ants, consume native invertebrates and 
seeds, and affect people by stinging them and infesting buildings. Some ant species ‘farm’ sap-
sucking scale insects that are pests of horticultural crops and native plants. Non-native ants can be 
introduced in pot plants, soil or among other materials. 

Yellow crazy ant (Anoplolepis gracilipes) has been detected in Darwin and Arnhem Land. Browsing 
ant (Lepisiota frauenfeldi) has been the subject of a national eradication program, including in 
Darwin and Kakadu in the NT. Other national eradication programs continue for red imported fire 
ant (Solenopsis invicta) in south-east Queensland and electric ant (Wasmannia auropunctata) in 
far north Queensland (Outbreak, 2024; Environment and Invasives Committee, 2019). The national 
eradication program for red imported fire ant has cost $596 million (Outbreak, 2023a). 

Diseases 

Examples of diseases that affect multiple species of native, ornamental and crop plants are myrtle 
rust and phytophthora (Phytophthora spp.). They can cause the death of plants, including 
established shrubs and trees. 

7.4.3 Preventing, responding to and managing biosecurity threats 

Biosecurity can be categorised into three broad approaches: 

•Prevention - taking measures to stop movement along pathways of spread, whether that be atthe international or state border, to and within a catchment, or between and within properties
•Incursion response - undertaking surveillance to detect new pests, weeds or diseases andattempting eradication upon detection, where feasible and cost-beneficial to do so
•Ongoing management – managing a pest, weed or disease that is firmly established in an area(i.e. is not feasible to eradicate), with control measures regularly applied to contain furtherspread and/or mitigate impacts.


The invasion curve (Figure 7-13) is commonly used as a visual representation of biosecurity actions 
taken at various stages of pest invasion. It applies at any scale from national down to an individual 
property. Prevention and eradication generally cost far less than the ongoing management which 
is needed for widely established species (i.e. containment and impact mitigation), although 
improved management tools may substantially reduce long-term costs. 


 

For more information on this figure please contact CSIRO on enquiries@csiro.au
Figure 7-13 The invasion curve with biosecurity actions taken at various stages 

Source: J. Virtue 

Shared responsibility at all levels 

Effective biosecurity requires a collaborative approach between government, industry and 
community, from the organisational to the individual level. Such ‘shared responsibility’ includes 
taking action to limit the risk of entry and spread of new pests, weeds and diseases, routinely 
looking for incursions and reporting high-risk species if and when detected, and collaborating in 
coordinated control programs across land tenures. Everyone has a duty of care (whether legal or 
moral) to not pose a biosecurity risk to others, including to not harbour invasive species that may 
threaten economic, environmental, social or cultural impacts to neighbouring land uses. 

The NT’s biosecurity system (NT Government, 2016) is nested in the national biosecurity system of 
Australia’s border quarantine and states’ and territory’s domestic quarantine and control program 
arrangements (DAFF, 2022a). Broadly defined, the national biosecurity system consists of the 
combined Australian, state and territory governments’ biosecurity legislative frameworks that 
seek to prevent pests, weeds and diseases entering, establishing, spreading and having an impact 
in Australia. It involves cooperation and collaboration between jurisdictions, and working with and 
supporting industry and community to involve multiple organisations across Australia as 
biosecurity partners. Various national agreements, plans and governance arrangements drive this 
shared responsibility ethos. 

The following sections describe prevention, incursion response and ongoing management 
activities for plant industries, aquaculture and invasive species in the Victoria catchment, within 
local, NT and national contexts. 


Biosecurity in plant industries 

Farm biosecurity planning 

In practice, most plant industry biosecurity activities – whether prevention, preparedness, 
surveillance, elimination, containment or ongoing management – occur at the property level. This 
level is where the relationship between expenditure on crop protection and maintaining profit-
driven productivity and market access is most direct. 

Developing and implementing a farm biosecurity plan is an effective means to prevent the 
introduction and establishment of new pests, weeds and diseases, and to limit the spread and 
impacts of those that are already established. Standard guidance is available on developing such 
plans (AHA and PHA, n.d.), which cover hygiene practices for pathways of introduction 
(e.g. certified seed, machinery and vehicle washdowns, restricted movement of visitors), routine 
surveillance and quick responses to any on-farm identified biosecurity risks. Associated with 
implementing these are signage (e.g. Figure 7-14), staff training, mapping, visitor management, 
record keeping, reporting and annual activity planning. 

A farm biosecurity plan is informed by the key biosecurity threats to the crops being grown, and 
broader invasive species risks. A plan should cover both incursion risks and those pests, weeds and 
diseases already present. It also needs to align with government regulatory requirements and 
industry standards. 

 

For more information on this figure please contact CSIRO on enquiries@csiro.au
Figure 7-14 Farm biosecurity signage available through farmbiosecurity website 


Regulatory prevention 

Government regulation and policy for plant biosecurity in the Victoria catchment are primarily 
governed by the Northern Territory Plant Health Act 2008. Specific legal requirements are 
summarised in the Northern Territory plant health manual (NT Government, 2023), which lists 
currently declared pests and diseases (and those that must be reported if detected in the NT), and 
associated entry conditions for all commercial and non-commercial movement of plants and plant 
products. 

For example, the NT restricts the entry of maize and soybean seed due to disease risks and the 
entry of nursery stock due to risk of introducing scale insects and sucking insects. Soil attached to 
used farm machinery, containers and earth-moving machinery may carry pests or diseases such as 
nematodes, snails, Phytophthora or Fusarium. Hence these items are legally required to be clean 
of soil, and a permit may be required for their entry into NT. In relation to used machinery for 
cotton production, the NT seeks to retain its ‘area freedom’ status for cotton fusarium wilt 


(Fusarium oxysporum f. sp. vasinfectum), which is established in cotton-growing areas in 
Queensland and NSW (Le et al., 2020). 

To access interstate markets, produce must meet the respective quarantine specifications and 
protocols, so that pests or diseases declared in those jurisdictions are not inadvertently 
introduced. This typically requires an inspection and the issue of a certificate verifying that 
conditions have been met, or that the property is in an area known to be free of a specific pest of 
concern (NT Government, 2023). For example, South Australia has movement restrictions (as of 
March 2024) on the entry of melons and other hosts of melon thrips (Thrips palmi) from 
jurisdictions where it is known to occur, including the NT (PIRSA, 2024). Current information on 
moving plant goods interstate is compiled on the Australian Interstate Quarantine website 
(Subcommittee on Domestic Quarantine and Market Access, 2024). 

Exports to overseas markets must meet Australian standards and any additional entry 
requirements from the importing countries for the products (DAFF, 2024b). This includes 
certification and supporting documentation relating to area freedom and/or treatments applied 
for specific pests, weeds and/or diseases. Depending on the country, there also may be maximum 
residue limits, or even nil tolerances, for specific pesticides. Exports are regulated by the 
Australian Government through the Commonwealth’s Export Control Act 2020 and associated 
rules for particular produce and products. 

Incursion response 

Most plant industries have national biosecurity, surveillance and/or preparedness plans for high-
risk exotic pests and diseases that pose national incursion risks (PHA, 2024a). Entry of these pests 
and diseases into Australia is prevented by the Australian Government’s pre-border and border 
quarantine requirements under the Commonwealth Biosecurity Act 2015. The Australian 
Government’s Northern Australia Quarantine Strategy is an ongoing surveillance program that 
seeks to detect incursions from countries to Australia’s north (DAFF, 2024a). 

Plant Health Australia (PHA) is the custodian of the Emergency Plant Pest Response Deed (EPPRD; 
Anon., 2024), which specifies how governments and affected industries undertake collaborative 
national eradication responses, including cost sharing and decision making. PLANTPLAN provides 
accompanying national guidelines for managing responses to emergency plant pest incidents at 
national, state or territory, and local levels (PHA, 2022). For example, banana freckle (Phyllosticta 
cavendishii) is currently the subject of an EPPRD national eradication program in the NT (Outbreak, 
2023b). 

Ongoing management 

Best management practice guides for control of established pests, weeds and diseases are 
available through the research and development corporations, other industry organisations and 
state primary industries departments, with some specific to cropping in northern Australia (e.g. NT 
Government, 2014; NT Farmers, 2022). These extension materials focus on integrated 
management approaches that combine a range of control practices (e.g. chemical, physical and 
biological control methods). The cotton industry also has a broader online best management 
practice assurance system (myBMP, 2024), which includes modules on integrated pest 
management and pesticide management. Additionally, the Grains Farm Biosecurity Program is an 


initiative to improve the management of, and preparedness for, biosecurity risks in the grains 
industry at the farm and industry levels (PHA, 2024b). 

Pesticides must be approved for use by the Australian Pesticides and Veterinary Medicines 
Authority (APVMA) and applied in a manner that aligns with requirements of the NT’s Agricultural 
and Veterinary Chemicals (Control of Use) Act 2004. This includes minimising spray drift, following 
label requirements for work health and safety, and ensuring appropriate applicator skills and 
licences. There are maximum permissible levels for certain pesticides in specified agricultural 
produce, achieved by following pesticide label requirements (or a Australian Pesticides and 
Veterinary Medicines Authority permit) regarding approved crops, rates and frequency of 
application, and withholding periods (NT Government, 2024c). 

A key consideration for ongoing management on-farm is ensuring chemical control tools are used 
tactically to limit the risk of developing insecticide, herbicide and fungicide resistance (Grains 
Research and Development Corporation, 2024; CropLife Australia, 2021). For example, growers 
cultivating Bollgard® 3 and Roundup Ready Flex® cotton must follow on-farm stewardship 
packages (Bayer, 2023). 

Growers whose crop production is affected by native animals may require NT Government permits 
before taking any lethal control measures. On-property storage of harvested grain needs 
consideration of physical and chemical means to prevent beetle and weevil pests (Grain Storage 
Extension Project, 2024). 

Biosecurity in aquaculture 

Plan for prevention 

Prevention in aquaculture starts with enterprise-level biosecurity planning. This is vital in 
protecting aquaculture facilities from diseases and parasites, which can be difficult to eliminate, 
let alone manage, once established. Planning guides have been developed for various industries, 
including barramundi (Landos et al., 2019) and oyster hatcheries. Preventing entry of pathogens 
into facilities is vital. Growers need to understand the various disease risks and where they could 
come from. Wild-captured broodstock poses a very high risk of introducing endemic diseases; 
stock known to be free from specific diseases should be sourced (Cobcroft et al., 2020). Diseases 
may enter a facility through contaminated equipment, workers handling diseased fish, water that 
is harbouring pathogens, or wild animals such as birds entering ponds (Irvin et al., 2018). 
Untreated source water is a key pathway for disease entry, with pathogen risks coming from wild 
stocks or, potentially, a nearby upstream aquaculture facility (Irvin et al., 2018). Pathogen 
monitoring should be ongoing, and emergency response plans should be developed to isolate any 
detected disease occurrence and implement thorough disinfestation procedures. 

Commercial aquaculture is regulated through the Northern Territory Fisheries Act 1998, and the 
Northern Territory Fisheries Regulations 1992. The Regulations prohibit movement or sale of 
diseased fish and require reporting of any legally notifiable diseases detected in aquaculture 
facilities. Movement of all stock is under a permit system, and health assessments are conducted 
to manage the risk of disease movement through movement of aquaculture stock. 


Incursion response 

AQUAPLAN is the national aquatic animal health strategic plan; it aims to improve border, 
enterprise and regional biosecurity measures, and build surveillance, diagnostic capacity and 
emergency preparedness (DAFF, 2022b). There is also national policy guidance on minimising the 
movement of disease when translocating live aquatic animals for aquaculture and other purposes 
(DAWE, 2020b). 

The NT Government can declare a control area in the event of an actual or likely notifiable disease 
outbreak in an aquaculture facility, providing for limits on further fish movement, halting the 
release of aquaculture water, and/or requiring mandatory treatment or destruction measures for 
fish and contaminated equipment. 

Having aquaculture biosecurity plans is not just about protecting the enterprise. There is also a 
duty of care to protect nearby wild fisheries which may be exposed to disease from discharge 
waters, escapee infected animals or fish movement via predatory birds. Prompt isolation of 
affected ponds and preventing water flow from these to the surrounding environment are vital in 
the event of a disease outbreak. The escape of white spot syndrome virus from prawn farms in 
Queensland and NSW led to restrictions on commercial and recreational fishing of crustaceans in 
adjacent catchments, with substantial local economic impacts. 

Ongoing management 

Treatment options are limited for aquatic diseases, particularly viral pathogens. Veterinary 
medicines, such as antibiotics for bacterial disease in barramundi, are available. However, their 
use can require veterinary permission in order to manage risks of antimicrobial resistance, both in 
the aquaculture facility itself and the broader food chain. Fungal and external protozoan 
pathogens may be able to be suppressed using altered salinity bathing. Most fundamentally is the 
need for a high-quality rearing environment, with optimal water conditions and feed supply, to 
reduce the risk of stress-induced disease outbreaks (Irvin et al., 2018). 

Biosecurity for invasive species 

Irrigation development planning 

Regional and local irrigation and industry infrastructure development, including road networks, 
should include prevention and management of invasive species in their environmental planning 
processes. This includes meeting legal obligations under the various Acts already mentioned, a 
stocktake of present distribution of declared species, and risk mitigation to limit pathways of 
introduction of new invasive species during construction and ongoing maintenance. Ongoing 
monitoring should be implemented for terrestrial and aquatic pests (vertebrate and invertebrate), 
and weeds. 

Weeds 

The Victoria catchment is within the scope of the Katherine Regional Weeds Strategy (NT 
Government, 2021) which collates the priority declared weed control programs, as coordinated by 
the NT Government. Under the Northern Territory Weeds Management Act 2001 every landholder 
is legally obliged to take all reasonable measures to prevent land being infested with a declared 
weed and to prevent a declared weed from spreading. There are also prohibitions on buying, 
selling, cultivating, moving or propagating any declared weed, and a legal requirement to notify a 


declared weed’s presence if it is new to a property. Certain declared plants, such as gamba grass, 
neem (Azadirachta indica) and bellyache bush (Jatropha gossypiifolia) also have statutory 
management plans. 

The NT Government website and other Australian websites (e.g. www.weeds.org.au) provide best 
management practice information on how to control declared weeds and other invasive plants, 
including registered herbicides and biological control agents. In particular, much information is 
available on management on WoNS (CISS, 2021). 

In selecting new crops and pastures for planting in the Victoria catchment, landholders should 
consider their crops’ weed risks to the surrounding environment. An example method for 
considering weed risks is the Western Australian Government’s environmental weed risk 
assessment process for plant introductions to pastoral lease land (Moore et al., 2022). Many 
northern Australia pasture grasses can be invasive, and cause significant biodiversity and cultural 
impacts in the landscape (Australian Government, 2012). 

Cotton is not considered to pose a significant environmental weed threat in northern Australia 
(Office of the Gene Technology Regulator, 2024). It has been sporadically recorded across 
northern Australia on roadsides, near cropping fields, in irrigation drains and adjacent to natural 
watercourses (Atlas of Living Australia, 2024). However, modern varieties’ ability to establish and 
reproduce is constrained by dense lint around seeds impeding germination, seed predation, 
seasonal drought, competition from established plants, herbivory and fire (Eastick and Hearnden 
2006; Rogers et al., 2007). Nonetheless, it is recommended that transport of harvested cotton is 
covered to reduce the likelihood of spread outside cultivation (Addison et al., 2007). 

Terrestrial vertebrate pests 

Large feral herbivores are controlled through mustering, trapping, baiting and/or aerial or ground 
shooting programs, depending on the approved humane control methods for particular species 
(CISS, 2024; NT Government, 2024d). For long-term suppression, programs need to be conducted 
over multiple years at a subregional scale across all infested properties, taking account of animal 
movements and subpopulations. Ongoing control is then needed to maintain low densities. 

7.5 Off-site and downstream impacts 

7.5.1 Introduction 

Northern Australian river systems are distinctive as they have highly variable flow regimes, unique 
species composition, low human population densities and, in some cases, naturally high turbidity 
(Brodie and Mitchell, 2005). Primary influences on groundwater and surface water quality include 
increased sediment loads associated with land clearing, grazing, agriculture and late dry-season 
fires, and nutrient pollution from agricultural and pastoral land use (Dixon et al., 2011). These can 
affect the water quality of not just groundwater and rivers, lakes and wetlands but also estuarine 
and marine ecosystems. 

The principal pollutants from agriculture are nitrogen, phosphorus, total suspended solids, 
herbicides and pesticides (Lewis et al., 2009; Kroon et al., 2016; Davis et al., 2017). Water losses 
via runoff or deep drainage are the main pathways by which agricultural pollutants enter water 


bodies. The type and quantity of pollutants lost from an agricultural system and ultimately the 
quality of the receiving surface and groundwater is significantly influenced by a wide range of 
factors, including environment factors such as climate, hydrology, soils, hydro geochemistry and 
topography as well as land use and management factors such as crops, cropping system, method 
of application of irrigation water, tailwater management, quality of source water, location and 
proximity to drainage lines and conservation and irrigation practices. Due to the high dependency 
of the location, design, implementation and operation of an irrigation development on water 
quality predicting water quality impacts associated with irrigated agriculture is very difficult. 
Rather the influence of these environment and management factors on water quality are 
discussed in more detail in the companion technical report on water quality (Motson et al., 2024). 

Most of the science in northern Australia concerned with the downstream impacts of agricultural 
development has been undertaken in the eastern-flowing rivers that flow into the Great Barrier 
Reef lagoon. Comparatively little research on the topic has been done in the rest of northern 
Australia and there is need for caution in transposing findings from north-eastern Australia, which 
is different in terms of climate, geomorphology and patterns of settlement to those parts of 
northern Australia west of the Great Dividing Range. Nonetheless experience from north-eastern 
Australia has been that the development of agriculture has been associated with declining water 
quality (Lewis et al., 2009; Mitchell et al., 2009; De’ath et al., 2012; Waterhouse et al., 2012; 
Thorburn et al., 2013; Kroon et al., 2016). Pollutant loads in north-eastern Australian rivers 
(typically those in which agriculture dominates as a land use) are estimated to have increased 
considerably since European settlement in the 1850s for nitrogen (2 to 9 times baseline levels), 
phosphorus (3 to 9 times), suspended sediment (3 to 6 times) and pesticides (~17,000 kg) (Kroon 
et al., 2016). 

7.5.2 Impacts of changes in water quality on aquatic ecosystems 

Degraded water quality can cause a loss of aquatic habitat, biodiversity, and ecosystem services. 
Increased nitrogen and phosphorus can cause plankton blooms and weed infestation, increase 
hypoxia (low oxygen levels) and result in fish deaths. Pesticides, used to increase agricultural 
productivity, can harm downstream aquatic ecosystems, flora and fauna. As with fertiliser 
nutrients, pesticides can enter surface water bodies and groundwater via infiltration, leaching, and 
runoff from rainfall events and irrigation. These chemicals can be toxic to non-target species, such 
as aquatic life and humans, affecting nervous systems, immune systems, photosynthesis and 
growth (Cantin et al., 2007; Kaur et al., 2019; Naccarato et al., 2023). They can be carcinogenic 
(Mohanty and Jena, 2019) and cause multiple sub-lethal effects that can disrupt the ecological 
balance of aquatic systems and degrade aquatic communities (Giglio and Vommaro, 2022; Miller 
et al., 2020; Wang et al., 2022). 

Other water quality variables that can have a significant effect on the health of aquatic species, 
communities and ecosystems include salinity, pH, and suspended sediments. Increased salinity, 
indicated by increased EC and TDS, can interfere with osmoregulatory processes, harming those 
species not adapted to saline conditions (Hart et al., 2003). Variations in the pH of a water body 
can negatively affect an organism’s biochemical processes, leading to altered behaviour, 
functioning, growth, and even survival (U.S. EPA, 2024). In aquatic ecosystems, elevated loads of 
suspended sediment can smother habitats and benthic invertebrates, affect the feeding and 


respiratory systems of aquatic species, and reduce light penetration, affecting photosynthetic 
activity (Chapman et al., 2017). 

Table 7-8 Water quality variables reviewed – their impacts on the environment, aquatic ecology and human health 

WATER 
QUALITY 
VARIABLE



THREATS TO AQUATIC ECOLOGY AND HUMAN HEALTH

REFERENCE 

Nutrients 

Nitrogen 

Forms of nitrogen in freshwater systems include: nitrate (NO3), nitrite 
(NO2), ammonia (NH3) and ammonium (NH4). 

In excessive quantities, contributes to eutrophication and algal 
blooms, which can deplete oxygen and create hypoxic/anoxic 
conditions harmful to aquatic life. 

Health threat to humans, particularly infants, and mammals 

Carpenter et al. 
(1998) 

Phosphorus 

High concentrations may lead to eutrophication and algal blooms, 
which can deplete oxygen and create hypoxic/anoxic conditions 
harmful to aquatic life 

Mainstone and 
Parr (2002) 

Dissolved Organic 
Carbon 

A proxy for dissolved organic matter, affecting water clarity, 
temperature, biogeochemical processes, food webs and ecosystem 
productivity. Dissolved Organic Carbon may exacerbate 
eutrophication and hypoxia in aquatic ecosystems, and cause 
problems in drinking water treatment processes 

Palviainen et al. 
(2022) 

Pesticide 
groups 

Arylurea 

Includes pesticides such as Diuron® and tebuthiuron. May inhibit 
photosynthesis in plants and aquatic species. These pesticides are less 
soluble in water and better absorbed by the soil 

Cantin et al. 
(2007), Fojut et al. 
(2012) 

Carbamates 

Broad-spectrum pesticides that affect nerve impulse transmission and 
are highly toxic to vertebrate species. Suspected carcinogens and 
mutagens. Relatively low persistence; not easily adsorbed to soil 
particles 

Kaur et al. (2019), 
Rad et al. (2022) 

Chloroacetanilides 

Affects cell division, disrupting aquatic plant growth; also toxic to 
aquatic insects. Persistent. Low binding affinity to soil particles but 
highly water soluble; therefore, it has a high capacity for leaching into 
the groundwater and ending up in surface water. Carcinogens with 
moderate to high chronic toxicity 

ANZG (2020), 
Mohanty and Jena 
(2019) 

Dinitroanilines 

Broad-spectrum herbicides with low water solubility; considered non-
mobile in soil. Affect seed germination and root growth in plants. 
Variable, species-specific toxicity ranging from slightly to highly acute. 
Hazardous to animals and humans in sub-lethal concentrations. 
Known bioaccumulation in and acute toxicity to aquatic organisms 

Giglio and 
Vommaro (2022) 

Neonicotinoids 

Highly toxic to invertebrates, particularly aquatic insects. Sub-lethal 
toxicity in fish. High solubility. High chronic risk to global freshwater 
ecosystems. Suspected to be carcinogenic 

Wang et al. (2022) 

Organochlorines 

Persistent organic pollutants that can bioaccumulate in fatty tissues. 
These pesticides are toxic to humans and other animals, and they are 
highly toxic to most aquatic life 

DCCEEW (2021) 
Kaur et al. (2019) 

Phenylpyrazole 

These pesticides disrupt nerve impulse transmission. Toxic to aquatic 
organisms and birds. Phenylpyrazole pesticides, such as Fipronil, have 
been found to degrade stream communities. Moderate water 
solubility and hydrophobicity. Slightly mobile in soils. Moderate 
persistence 

Gao et al. (2020), 
Miller et al. (2020) 

Triazine 

Inhibits photosynthesis in plants, potentially leading to reduced plant 
growth and blocks food intake by insect pests. Short to moderate 

Naccarato et al. 
(2023) 




WATER 



THREATS TO AQUATIC ECOLOGY AND HUMAN HEALTH

REFERENCE 

persistence depending on soil pH. Adverse and sub-lethal effects on 
terrestrial and aquatic non-target organisms, affecting growth and 
the nervous and immune systems 

Salinity 



Can affect osmoregulatory processes of aquatic species, harming 
aquatic life not adapted to saline water. Significant increases in 
salinity may compromise the integrity of freshwater ecosystems 

Hart et al. (2003) 

Other 

Total Suspended 
Solids 

Can smother habitats, reduce light penetration (through increasing 
turbidity), and affect the feeding and respiratory systems of aquatic 
organisms 

Chapman et al. 
(2017) 

pH 

Variations can negatively affect aquatic life stages, affecting their 
biochemical processes. Preferred pH range of 6.4–8.4 for aquatic 
species 

U.S. E.P.A (2024) 



7.5.3 Impacts of irrigated agriculture on water quality 

Fertiliser applications in irrigated agriculture can significantly affect nutrient levels in drainage 
waters, leading to increased concentrations of total phosphorous (TP) and total nitrogen (TN) in 
surface waters during the irrigation season (Barbieri et al., 2021; Mosley and Fleming, 2010). The 
type of cropping system employed also plays a crucial role in determining groundwater nutrient 
concentrations. For example, variations in cropping practices, such as mulch-till versus ridge-till 
systems, can result in substantial differences in nitrate levels, underscoring the importance of 
adopting best management practices for protecting groundwater quality (Albus and Knighton, 
1998). 

Surface water quality is similarly affected by nutrient inputs, with concentrations of TP often 
decreasing as streamflow increases, suggesting a dilution effect (Skhiri and Dechmi, 2012). 
However, this relationship can be inconsistent, as dilution effects may not be evident when only 
storm event streamflow is considered. Instead, TP concentrations are influenced by a combination 
of factors, including rainfall duration and intensity, as well as irrigation and fertiliser application 
practices. The interplay of these factors highlights the complex interactions between rainfall, 
irrigation, and nutrient management in determining both surface water and groundwater quality 
outcomes. 

Controlled pesticide use is crucial for managing its impact on surface water quality. When 
pesticide application rates are managed and irrigation schedules are aligned with crop growth 
stages, their concentrations are typically low. Pesticide-specific application practices also influence 
runoff concentrations: pesticides that are applied to, and therefore intercepted by, the crop 
canopy have significantly lower surface water concentrations relative to those applied to bare soil 
(Moulden et al., 2006). 

Seasonal hydrology, particularly ‘first-flush’ events following irrigation or significant rainfall, plays 
a critical role in determining water quality (Davis et al., 2013; Yeates, 2016). Studies have shown 
that pesticide concentrations in runoff are highest following initial irrigation events but decrease 
in subsequent events (Davis et al., 2013). Despite this dilution, pesticide concentrations in 
receiving waters can still exceed recommended levels. Similarly, nitrogen concentrations in runoff 
are often higher following early-season rainfall, when crops have not yet fully absorbed available 
nitrogen, leading to increased transport in runoff (Yeates, 2016). 


These findings underscore the importance of implementing sustainable irrigation management 
practices and highlight the need for continuous monitoring and adaptive management to mitigate 
the impacts of agricultural activities on water quality. Ensuring effective management is vital for 
protecting water resources and maintaining the ecological integrity of aquatic ecosystems and 
communities amid agricultural intensification. 

The potential for irrigated agriculture to cause secondary salinisation is discussed in Section 7.6. 

Managing irrigation drainage 

Surface drainage water is water that runs off irrigation developments as a result of over-irrigation 
or rainfall. This is mostly an issue where water is applied using surface irrigation methods 
(e.g. furrow, flood) rather than spray or micro-irrigation methods (e.g. drip, micro-spray). This 
excess water can potentially affect the surrounding environment by modifying flow regimes and 
changing water quality. Hence, management of irrigation or agricultural drainage waters is a key 
consideration when evaluating and developing new irrigation systems and should be given careful 
consideration during the planning and design processes. Regulatory constraints on the disposal of 
agricultural drainage water from irrigated lands are being made more stringent as this disposal can 
potentially have significant off-site environmental effects (Tanji and Kielen, 2002). Hence, 
minimising drainage water through the use of best-practice irrigation design and management 
should be a priority in any new irrigation development in northern Australia. This involves 
integrating sound irrigation systems, drainage networks and disposal options so as to minimise 
off-site impacts. 

Surface drainage networks must be designed to cope with the runoff associated with irrigation, 
and also the runoff induced by rainfall events on irrigated lands. Drainage must be adequate to 
remove excess water from irrigated fields in a timely manner and hence reduce waterlogging and 
potential salinisation, which can seriously limit crop yields. In best-practice design, surface 
drainage water is generally reused through a surface drainage recycling system where runoff 
tailwater is returned to an on-farm storage or used to irrigate subsequent fields within an 
irrigation cycle. 

The quality of drainage water depends on a range of factors including water management and 
method of application, soil properties, method and timing of fertiliser and pesticide application, 
hydrogeology, climate and drainage system (Tanji and Kielen, 2002). These factors need to be 
taken into consideration when implementing drainage system water recycling and also when 
disposing of drainage water to natural environments. 

A major concern with tailwater drainage is the agricultural pollutants derived from pesticides and 
fertilisers that are generally associated with intensive cropping and are found in the tailwater from 
irrigated fields. Crop chemicals can enter surface drainage water if poor water application 
practices or significant rainfall events occur after pesticide or fertiliser application (Tanji and 
Kielen, 2002). Thus, tailwater runoff may contain phosphate, organic nitrogen and pesticides that 
have the potential to adversely affect flora and fauna and ecosystem health, on land and in 
waterways, estuaries or marine environments. Tailwater runoff may also contain elevated levels of 
salts, particularly if the runoff has been generated on saline surface soils. Training irrigators in 
responsible application of both water and agrochemicals is therefore an essential component of 
sustainable management of irrigation. 


As tailwater runoff is either discharged from the catchment or captured and recycled, it can result 
in a build-up of agricultural pollutants that may ultimately require disposal from the irrigation 
fields. In externally draining basins, the highly seasonal nature of flows in northern Australia does 
offer opportunities to dispose of poor-quality tailwater during high-flow events. However, 
downstream consequences are possible, and no scientific evidence is available to recommend 
such disposal as good practice. Hence, consideration should be given to providing an adequate 
understanding of the downstream consequences of disposing of drainage effluent, and options 
must be provided for managing disposal that minimise impacts on natural systems. 

7.5.4 Natural processing of water contaminants 

While elevated contaminants and water quality parameters can harm the environment and human 
health, there are several processes by which aquatic ecosystems can partially process 
contaminants and regulate water quality. Denitrification, for example, is the process of anaerobic 
microbial respiration which, in the presence of carbon, reduces nitrogen to nitrous oxide and 
dinitrogen gas (Martens, 2005). Therefore, denitrification is a naturally occurring process that can 
remove and reduce nitrogen concentrations within a water body. Pesticides can also be naturally 
removed from water via chemical oxidation, microbial degradation, or ultraviolet photolysis, 
although some chemically stable pesticides are highly persistent, and their microbial degradation 
is slow (Hassaan and El Nemr, 2020). Phosphorus, however, does not have a microbial reduction 
process equivalent to denitrification. Instead, if it is not temporarily taken up by plants, 
phosphorus can be adsorbed onto the surface of inorganic and organic particles and stored in the 
soil, or deposited in the sediments of water bodies, such as wetlands (Finlayson, 2022). This 
phosphorus can be remobilised into solution and re-adsorbed, resulting in ‘legacy’ phosphorus 
that can affect water quality for many years (Records et al., 2016). 

7.5.5 Water quality considerations relevant to aquaculture 

Aquaculture can be impacted by poor water quality and can also contribute to poor water quality 
unless aquaculture operations are well managed. A summary is provided below, however, for 
more information see Northern Australia Water Resource Assessment report on aquaculture 
viability (Irvin et al., 2018). 

Chemical contaminant risk to aquaculture and the environment 

Hundreds of different chemicals, including oils, metals, pharmaceuticals, fertilisers and pesticides 
(i.e. insecticides, herbicides, fungicides), are used in different agricultural, horticultural and mining 
sectors, and in industrial and domestic settings, throughout Australia. Releasing these chemical 
contaminants beyond the area of target application can contaminate soils, sediments and waters 
in nearby environments. In aquatic environments, including aquaculture environments, fertilisers 
have the potential to cause non-point source pollution. Eutrophication is caused by nutrients that 
trigger excessive growth of plant and algal species, which then form hypoxic ‘dead zones’ and 
potentially elevated levels of toxic un-ionised ammonia (Kremser and Schnug, 2002). This can have 
a significant impact on the health and growth of animals in aquaculture operations, as well as in 
the broader environment. 


Of concern to aquaculture in northern Australia are the risks posed to crustaceans (e.g. prawns 
and crabs) by some of the insecticides in current use. These are classified based on their specific 
chemical properties and modes of action. The different classes of insecticides have broad and 
overlapping applications across different settings. 

The toxicity of organophosphate insecticides is not specific to target insects, raising concerns 
about the impacts on non-target organisms such as crustaceans and fish. Despite concerns about 
human health impacts and potential carcinogenic risks, organophosphates are still one of the most 
broadly used types of insecticide globally, and they are still used in Australia for domestic pest 
control (Weston and Lydy, 2014; Zhao and Chen, 2016). Pyrethroid insecticides have low toxicity 
to birds and mammals, but higher toxicity to fish and arthropods. Phenylpyrazole insecticides also 
pose risks to non-target crustaceans (Stevens et al., 2011). Neonicotinoid insecticides are being 
used in increasing amounts because they are very effective at eliminating insect pests, yet they 
pose low risks to mammals and fish (Sánchez-Bayo and Hyne, 2014). Monitoring data from the 
Great Barrier Reef catchments indicate that the concentration of neonicotinoid insecticides in 
marine water samples is rapidly increasing with widespread use. One significant concern for 
aquaculture is the risk that different insecticides, when exposed to non-target organisms, may 
interact to cause additive or greater-than-additive toxicity. 

Aquaculture discharge water and off-site impacts 

Discharge water is effluent from land-based aquaculture production (Irvin et al., 2018). It is water 
that has been used (culture water) and is no longer required in a production system. In most 
operations (particularly marine), bioremediation is used to ensure that water discharged off-farm 
into the environment contains low amounts of nutrients and other contaminants. The aim is for 
discharge waters to have similar physiochemical parameters to the source water. 

Discharge water from freshwater aquaculture can be easily managed and provides a water 
resource suitable for general or agriculture-specific irrigation. Discharge water from marine 
aquaculture is comparatively difficult to manage and has limited reuse applications. The key 
difference in discharge management is that marine (salty) water must be discharged at the source, 
whereas the location for freshwater discharge is less restrictive and potential applications 
(e.g. irrigation) are numerous. Specific water discharge guidelines vary with aquaculture species 
and jurisdiction. For example, Queensland water discharge policy minimum standards for prawn 
farming include standards for physiochemical indicators (e.g. oxygen and pH) and nutrients 
(e.g. nitrogen, phosphorus and suspended solids) and total volume (EHP, 2013). 

The volume of water required to be discharged or possibly diverted to a secondary application 
(e.g. agriculture) is equivalent to the total pond water use for the season minus total evaporative 
losses and the volume of recycled water used during production. 

A large multidisciplinary study of intensive Australian prawn farming, which assessed the impact of 
effluent on downstream environments (CSIRO, 2013), found that Australian farms operate under 
world’s best practice for the management of discharge water. The study found that discharge 
water had no adverse ecological impact on the receiving environment and that nutrients could not 
be detected 2 km downstream from the discharge point. 

While Australian prawn farms are reported as being among the most environmentally sustainable 
in the world (CSIRO, 2013), the location of the industry adjacent to the World Heritage listed Great 


Barrier Reef and related strict policy on discharge has been a major constraint to the industry’s 
expansion. Strict discharge regulation, which requires zero net addition of nutrients in waters 
adjacent to the Great Barrier Reef, has all but halted expansion in the last decade. An example of 
the regulatory complexity in this region is the 14-year period taken to obtain approval to develop a 
site in the Burdekin shire in north Queensland (APFA, 2016). 

In a report to the Queensland Government (Department of Agriculture and Fisheries Queensland, 
2013), it was suggested that less-populated areas in northern Australia, which have less conflict for 
the marine resource, may have potential as areas for aquaculture development. The complex 
regulatory environment in Queensland was a factor in the decision by Project Sea Dragon to 
investigate greenfield development in WA and NT as an alternative location for what would be 
Australia’s largest prawn farm (Seafarms, 2016). 

Today, most farms (particularly marine) use bioremediation ponds to ensure that water 
discharged off-farm into the environment contains low amounts of nutrients and other 
contaminants. The prawn farming industry in Queensland has adopted a code of practice to 
ensure that discharge waters do not result in irreversible or long-term impacts on the receiving 
environment (Donovan, 2011). 

7.6 Irrigation-induced salinity 

Salinity is the presence of soluble salts in soils or water. Salinity is the result of the complex 
interactions of geophysical and land use factors such as landscape features (geology, landform), 
climate, soil properties, water characteristics and land management. Salinity becomes a land use 
issue when the concentration of salts adversely affects plant establishment growth (crops, 
pastures or native vegetation) or degrades soil or affects water quality (Department of Natural 
Resources, 1997). 

The salts in the landscape are derived from salts delivered through rainfall, weathering of primary 
minerals and origin of the geology such as marine sediments. Most salinity outbreaks result from 
the imbalances in the hydrological systems of a landscape, including secondary salinity due to man 
related activities such as clearing of native vegetation, cropping and irrigation. 

Naturally occurring areas of salinity or ‘primary salinity’ occur in the landscape with ecosystems 
adapted to these conditions. In a dryland salinity (non-irrigated) hazard mapping of the NT, Tickell 
(1994) determined that the dryland salinity hazard over most of the NT is low, predominantly due 
to relatively low salt storages occurring in the landscape were mainly due to small salt inputs from 
rainfall. 

Natural salinity in the Victoria catchment is confined to the freshwater springs originating from the 
dolomites on Kidman Springs; on shales in the West Baines catchment; and on the marine plains at 
the mouth of the Victoria River which are subject to tidal inundation. The springs and associated 
discharge areas on Kidman Springs have very high salt concentrations (mainly calcium salts) on the 
soil surface and are unsuitable for development. All moderately deep to very deep soils developed 
on the Proterozoic shales in the West Baines catchment are naturally high in subsoil salts with 
minor natural salinity in scarp retreat areas below quartz sandstone hills and plateaux. 


In Australia, excessive root-zone drainage through poor irrigation practices, together with leakage 
of water from irrigation distribution networks and drainage channels, has caused the watertable 
level to rise under many intensive irrigated areas. Significant parts of all major intensive irrigation 
areas in Australia are currently either in a shallow watertable equilibrium condition or approaching 
it (Christen and Ayars, 2001). Where shallow watertables containing salts approach the land 
surface (in the vicinity of 2–3 m from the land surface), salts can concentrate in the root zone over 
time through evaporation. The process by which salts accumulate in the root zone is accelerated if 
the groundwater also has high salt concentrations. 

In the case of irrigation-induced salinisation in the Victoria catchment, the landscapes suitable for 
irrigation development but at risk of secondary salinisation are restricted to the extensive 
Cenozoic clay plains (SGG 9); and the gently undulating plains with Sodosols (SGG 8), Chromosols 
(SGG 1) and Dermosols (SGG 2) developed on shales in the West Baines catchment. Clay soils 
(SGG 9) on the alluvial plains overlying the shales may also be at risk. These soils with heavy clay 
subsoils are naturally high in soluble salts in the subsoils. Irrigation may cause excessive deep 
drainage and raised watertables resulting in secondary salinisation. Other soils are generally not at 
risk from irrigation-induced salinity. 

Generic modelling results evaluating the risk of watertable rise are documented in the Flinders 
and Gilbert Agricultural Resource Assessment technical report on surface water – groundwater 
connectivity (Jolly et al., 2013). 

Further investigations on salinity processes and monitoring of watertables are necessary if these 
areas are to be developed. 

7.7 References 

AHA and PHA (n.d.) Farm biosecurity action planner. Animal Health Australia and Plant Health 
Australia, Canberra. Viewed 26 February 2024, Hyperlink to: Farm biosecurity action planner
. 

Albus WL and Knighton RE (1998) Water quality in a sand plain after conversion from dryland to 
irrigation: tillage and cropping systems compared. Soil and Tillage Research 48(3), 195–206. 

Anon. (2024) Government and Plant Industry Cost Sharing Deed in respect of Emergency Plant 
Pest Responses. Viewed 30 September 2024, Hyperlink to: Government and plant industry cost sharing deed in respect of emergency plant pest responses
. 

ANZG (2020) Toxicant default guideline values for aquatic ecosystem protection: Metolachlor in 
freshwater. Australian and New Zealand Guidelines for Fresh and Marine Water Quality. 
Viewed 8 September 2024, 
https://www.waterquality.gov.au/sites/default/files/documents/metolachlor_fresh_dgv-
technical-brief_0.pdf. 

Arthington AH, Balcombe SR, Wilson GA, Thoms MC and Marshall J (2005) Spatial and temporal 
variation in fish-assemblage structure in isolated waterholes during the 2001 dry season of 
an arid-zone floodplain river, Cooper Creek, Australia. Marine and Freshwater Research 
56(1), 25–35. 


Asbridge E, Lucas R, Ticehurst C and Bunting P (2016) Mangrove response to environmental 
change in Australia’s Gulf of Carpentaria. Ecology and Evolution 6(11), 3523–3539. 

Australian Government (2012) Threat abatement plan to reduce the impacts on northern 
Australia’s biodiversity by the five listed grasses. Australian Government Department of 
Climate Change, Energy, the Environment and Water. Viewed 27 February 2024, Hyperlink to: Threat abatement plan to reduce the impacts on northern Australia's biodiversity by the five listed grasses
. 

Australian Government and Northern Territory Government (n.d.) Freshwater pest identification 
guide. Australian Government Department of Agriculture and Water Resources and 
Northern Territory Government. Viewed 7 February 2024, Hyperlink to: Freshwater pest identification guide
. 

Bamford M (1992) The impact of predation by humans upon waders in the Asian/Australasian 
Flyway: evidence from the recovery of bands. Stilt, 38–40. 

Barbaree BA, Reiter ME, Hickey CM, Strum KM, Isola JE, Jennings S, Tarjan ML, Strong, CM, Stenzel 
LE, Shuford DW (2020) Effects of drought on the abundance and distribution of non-
breeding shorebirds in central California, USA. PLoS ONE 15(10): e0240931. 
https://doi.org/10.1371/journal.pone.0240931 

Barbieri MV, Peris A, Postigo C, Moya-Garcés A, Monllor-Alcaraz LS, Rambla-Alegre M, Eljarrat E 
and López de Alda M (2021) Evaluation of the occurrence and fate of pesticides in a typical 
Mediterranean delta ecosystem (Ebro River Delta) and risk assessment for aquatic 
organisms. Environmental Pollution 274, 115813. DOI: 10.1016/j.envpol.2020.115813. 

Bayer (2023) Bollgard 3 Resistance Management Plan (RMP) for Northern Australia. Viewed 26 
February 2024, Hyperlink to: Bollgard 3 Resistance Management Plan (RMP) for Northern Australia
. 

Bengsen AJ, Gentle MN, Mitchell JL, Pearson HE and Saunders GR (2014) Impacts and 
management of wild pigs Sus scrofa in Australia. Mammal Review 44(2), 135–147. Hyperlink to: Impacts and management of wild pigs Sus scrofa in Australia
. 

BirdLife International (2023) Important Bird Area factsheet: Legune (Joseph Bonaparte Bay). 
Viewed 27 November 2023, Hyperlink to: Important Bird Area factsheet: Legune (Joseph Bonaparte Bay)
. 

Blaber S, Brewer D and Salini J (1989) Species composition and biomasses of fishes in different 
habitats of a tropical northern Australian estuary: their occurrence in the adjoining sea and 
estuarine dependence. Estuarine, Coastal and Shelf Science 29(6), 509–531. 

Bradshaw CJA, Hoskins AJ, Haubrock PJ, Cuthbert RN, Diagne C, Leroy B, Andrews L, Page B, 
Cassey P, Sheppard AW and Courchamp F (2021) Detailed assessment of the reported 
economic costs of invasive species in Australia. NeoBiota 67, 511–550. Hyperlink to: Detailed assessment of the reported economic costs of invasive species in Australia
. 

Brewer D, Blaber S, Salini J and Farmer M (1995) Feeding ecology of predatory fishes from Groote 
Eylandt in the Gulf of Carpentaria, Australia, with special reference to predation on penaeid 
prawns. Estuarine, Coastal and Shelf Science 40(5), 577–600. 


Brodie JE and Mitchell AW (2005) Nutrients in Australian tropical rivers: changes with agricultural 
development and implications for receiving environments. Marine and Freshwater Research 
56(3), 279–302. 

Bunn SE and Arthington AH (2002) Basic principles and ecological consequences of altered flow 
regimes for aquatic biodiversity. Environmental Management 30(4), 492–507. 

Burford M, Valdez D, Curwen G, Faggotter S, Ward D and Brien KO (2016) Inundation of saline 
supratidal mudflats provides an important source of carbon and nutrients in an aquatic 
system. Marine Ecology Progress Series 545, 21–33. 

Burford MA and Faggotter SJ (2021) Comparing the importance of freshwater flows driving 
primary production in three tropical estuaries. Marine Pollution Bulletin 169, 112565. 

Burford MA, Revill AT, Palmer DW, Clementson L, Robson BJ and Webster IT (2011) River 
regulation alters drivers of primary productivity along a tropical river–estuary system. 
Marine and Freshwater Research 62(2), 141–151. Hyperlink to: River regulation alters drivers of primary productivity along a tropical river–estuary system
. 

Canham R, Flemming SA, Hope DD, Drever MC (2021) Sandpipers go with the flow: Correlations 
between estuarine conditions and shorebird abundance at an important stopover on the 
Pacific Flyway. Ecol Evol. 2021; 11: 2828–2841. https://doi.org/10.1002/ece3.7240 

Cantin NE, Negri AP and Willis BL (2007) Photoinhibition from chronic herbicide exposure reduces 
reproductive output of reef-building corals. Marine Ecology Progress Series 344, 81–93. 

Carpenter SR, Caraco NF, Correll DL, Howarth RW, Sharpley AN and Smith VH (1998) Nonpoint 
pollution of surface waters with phosphorus and nitrogen. Ecological Applications 8(3), 559–
568.DOI: 10.2307/2641247.

Chapman B, Henry R, Wurm P, Bellairs S, Crayn D, Smyth H, Furtado A, Sivapalan S, Ford R and 
Matchett T (2020) A situational analysis for developing a rice industry in Northern Australia. 
Project A.1.1718120, Cooperative Research Centre for Developing Northern Australia. 
Viewed 14 February 2024, Hyperlink to: A situational analysis for developing a rice industry in Northern Australia
. 

Chapman PM, Hayward A and Faithful J (2017) Total suspended solids effects on freshwater lake 
biota other than fish. Bulletin of Environmental Contamination and Toxicology 99(4), 423–
427.DOI: 10.1007/s00128-017-2154-y.

Chatto R (2006) The distribution and status of waterbirds around the coast and coastal wetlands of 
the Northern Territory. Technical Report 76. Parks and Wildlife Commission of the Northern 
Territory. Darwin, Australia. 

Christen EW and Ayars JE (2001) Subsurface drainage system design and management in irrigated 
agriculture: best management practices for reducing drainage volume and salt load. 
Technical report 38/01. CSIRO Land and Water, Griffith, NSW. 

CISS (2021) Profiles for Weeds of National Significance. Weeds Australia. Centre for Invasive 
Species Solutions. Viewed 13 March 2024, Hyperlink to: Profiles for Weeds of National Significance
. 

CISS (2024) Management toolkits. pestSMART. Centre for Invasive Species Solutions. Viewed 27 
February 2024, Hyperlink to: Management toolkits. pestSMART
. 


Clancy TF (2020) Wildlife Management Program for the Magpie Goose (Anseranas semipalmata) in 
the Northern Territory of Australia 2020–2030. Viewed 20 February 2024, Hyperlink to: Wildlife Management Program for the Magpie Goose (Anseranas semipalmata) in the Northern Territory of Australia 2020-2030
. 

Clemens RS, Weston MA, Haslem A, Silcocks A and Ferris J (2010) Identification of significant 
shorebird areas: thresholds and criteria. Diversity and Distributions, 16: 229-242. 
https://doi.org/10.1111/j.1472-4642.2009.00635.x 

Clemens R, Rogers DI, Hansen BD, Gosbell K, Minton CDT, Straw P, Bamford M, Woehler EJ, Milton 
DA, Weston MA, Venables B, Wellet D, Hassell C, Rutherford B, Onton K, Herrod A, Studds 
CE, Choi CY, Dhanjal-Adams KL, Murray NJ, Skilleter GA, Fuller, RA (2016) Continental-scale 
decreases in shorebird populations in Australia. Emu - Austral Ornithology, 116(2), 119–135. 
https://doi.org/10.1071/MU15056 

Cobcroft J, Bell R, Diedrich A, Jerry D and Fitzgerald J (2020) Northern Australia aquaculture 
industry situational analysis: project A.1. 1718119. CRC for Developing Northern Australia. 
Viewed 6 February 2024, Hyperlink to: Northern Australia aquaculture industry situational analysis study
. 

CRDC (2023) 2023–24 Cotton pest management guide. Cotton Research and Development 
Corporation. Viewed 19 February 2024, Hyperlink to: 2023-24 Cotton pest management guide
. 

Crook D, Buckle D, Allsop Q, Baldwin W, Saunders T, Kyne P, Woodhead J, Maas R, Roberts B and 
Douglas M (2016) Use of otolith chemistry and acoustic telemetry to elucidate migratory 
contingents in barramundi Lates calcarifer. Marine and Freshwater Research 68(8), 1554–
1566. 

Crook DA, Lowe WH, Allendorf FW, Erős T, Finn DS, Gillanders BM, Hadweng WL, Harrod C, 
Hermoso V, Jennings S, Kilada RW, Nagelkerken I, Hansen MM, Page TJ, Riginos C, Fry B and 
Hughes JM (2015) Human effects on ecological connectivity in aquatic ecosystems: 
integrating scientific approaches to support management and mitigation. Science in the 
Total Environment 534(2015), 52–64. 

Crook DA, Morrongiello JR, King AJ, Adair BJ, Grubert MA, Roberts BH, Douglas MM and Saunders 
TM (2022) Environmental drivers of recruitment in a tropical fishery: monsoonal effects and 
vulnerability to water abstraction. Ecological Applications, e2563. 

CropLife Australia (2021) Resistance management strategies Insecticides Fungicides Herbicides 
2021–2022. Viewed 20 March 2024, Hyperlink to: Resistance management strategies Insecticides Fungicides Herbicides 2021-2022
. 

CSIRO (2013) The environmental management of prawn farming in Queensland – worlds best 
practice. Viewed 27 September 2024, 
https://era.daf.qld.gov.au/id/eprint/2064/2/1._Prawn_farming_environmental_research_1995-2002-sec.pdf

DAFF (2022a) National Biosecurity Strategy. Australian Government Department of Agriculture, 
Fisheries and Forestry. Viewed 26 February 2024, 
https://www.biosecurity.gov.au/about/national-biosecurity-committee/nbs. 


DAFF (2022b) AQUAPLAN 2022–2027: Australia’s National Strategic Plan for Aquatic Animal 
Health. Australian Government Department of Agriculture, Fisheries and Forestry. Viewed 26 
February 2024, Hyperlink to: AQUAPLAN 2022–2027: Australia’s National Strategic Plan for Aquatic Animal Health
. 

DAFF (2023) Permitted live freshwater ornamental fish suitable for import. Australian Government 
Department of Agriculture, Fisheries and Forestry. Viewed 11 March 2024, Hyperlink to: Permitted live freshwater ornamental fish suitable for import
. 

DAFF (2024a) Northern Australia Quarantine Strategy (NAQS). Australian Government Department 
of Agriculture, Fisheries and Forestry. Viewed 11 March 2024, Hyperlink to: Northern Australia Quarantine Strategy (NAQS)
. 

DAFF (2024b) Exporting from Australia. Australian Government Department of Agriculture, 
Fisheries and Forestry. Viewed 20 March 2024, Hyperlink to: Exporting from Australia
. 

Davis A, Thorburn P, Lewis S, Bainbridge Z, Attard S, Milla R and Brodie J (2013) Environmental 
impacts of irrigated sugarcane production: herbicide run-off dynamics from farms and 
associated drainage systems. Agriculture, Ecosystems & Environment 180, 123–135. 

Davis AM, Pearson RG, Brodie JE and Butler B (2017) Review and conceptual models of agricultural 
impacts and water quality in waterways of the Great Barrier Reef catchment area. Marine 
and Freshwater Research 68, 1–19. DOI: 10.1071/MF15301. 

DAWE (2020a) Aquatic animal diseases significant to Australia: identification field guide. 5th 
edition. Australian Government Department of Agriculture, Water and the Environment. 
Viewed 10 March 2024, Hyperlink to: Aquatic animal diseases significant to Australia: identification field guide
. 

DAWE (2020b) National policy guidelines for the translocation of live aquatic animals. Australian 
Government Department of Agriculture, Water and the Environment. Viewed 
26 February 2024, Hyperlink to: National policy guidelines for the translocation of live aquatic animals
. 

DCCEEW (2021) Organochlorine pesticides (OCPs) – trade or common use names. Australian 
Government. Viewed 8 September 2024, 
https://www.dcceew.gov.au/environment/protection/publications/ocp-trade-names. 

De’ath G, Fabricius KE, Sweatman H and Puotinen M (2012) The 27-year decline of coral cover on 
the Great Barrier Reef and its causes. Proceedings of the National Academy of Sciences of 
the United States of America 109, 17995–17999. DOI: 10.1073/pnas.1208909109. 

Department of Natural Resources (1997) Salinity management handbook. Department of Natural 
Resources, DNRQ97109. Viewed 27 September 2024, 
https://www.publications.qld.gov.au/dataset/salinity-management-handbook 

Dixon I, Dobbs R, Townsend S, Close P, Ligtermoet E, Dostine P, Duncan R, Kennard M and 
Tunbridge D (2011) Trial of the Framework for the Assessment of River and Wetland Health 


(FARWH) in the wet–dry tropics for the Daly and Fitzroy Rivers, Tropical Rivers and Coastal 
Knowledge (TRaCK) research consortium. Charles Darwin University, Darwin. 

Driscoll, PV and Ueta, M (2002), The migration route and behaviour of Eastern Curlews Numenius 
madagascariensis. Ibis, 144: E119-E130. https://doi.org/10.1046/j.1474-919X.2002.00081.x 

Duke NC, Field C, Mackenzie JR, Meynecke J-O and Wood AL (2019) Rainfall and its possible 
hysteresis effect on the proportional cover of tropical tidal-wetland mangroves and 
saltmarsh–saltpans. Marine and Freshwater Research 70(8), 1047–1055. Hyperlink to Rainfall and its possible hysteresis effect on the proportional cover of tropical tidal-wetland mangroves and saltmarsh–saltpans
. 

Duke NC, Kovacs JM, Griffiths AD, Preece L, Hill DJ, Van Oosterzee P, Mackenzie J, Morning HS and 
Burrows D (2017) Large-scale dieback of mangroves in Australia’s Gulf of Carpentaria: a 
severe ecosystem response, coincidental with an unusually extreme weather event. Marine 
and Freshwater Research 68(10), 1816–1829. 

Durrell, SE dit (2000), Individual feeding specialisation in shorebirds: population consequences and 
conservation implications. Biological Reviews, 75: 503-518. https://doi.org/10.1111/j.1469-
185X.2000.tb00053.x 

Ebner BC, Millington M, Holmes BJ, Wilson D, Sydes T, Bickel TO, Power T, Hammer M, Lach L, 
Schaffer J, Lymbery A and Morgan DL (2020) Scoping the biosecurity risks and appropriate 
management relating to the freshwater ornamental aquarium trade across northern 
Australia. Centre for Tropical Water and Aquatic Ecosystem Research (TropWATER), James 
Cook University, Cairns. Viewed 20 March 2024, Hyperlink to: Scoping the biosecurity risks and appropriate management relating to the freshwater ornamental aquarium trade across northern Australia
. 

Environment and Invasives Committee (2019) National Invasive Ant Biosecurity Plan 2018–2028. 
Australian Government Department of Climate Change, Energy, the Environment and Water. 
Viewed 23 February 2024, Hyperlink to: National Invasive Ant Biosecurity Plan 2018-2028
. 

Finlayson CM, Lowry J, Bellio MG, Nou S, Pidgeon R, Walden D, Humphrey C and Fox G (2006) 
Biodiversity of the wetlands of the Kakadu Region, northern Australia. Aquatic Sciences 
68(3), 374–399. 

Finn PG, Catterall CP and Driscoll, PV (2007) Determinants of preferred intertidal feeding habitat 
for Eastern Curlew: A study at two spatial scales. Austral Ecology 32(2), 131-144. 

Finn PG & Catterall CP (2022). Towards an efficient indicator of habitat quality for Eastern Curlews 
on their intertidal feeding areas. Australasian Journal of Environmental Management, 30(1), 
26–47. https://doi.org/10.1080/14486563.2022.2084166 

Finn M and Jackson S (2011) Protecting Indigenous values in water management: a challenge to 
conventional environmental flow assessments. Ecosystems 14(8), 1232–1248. Hyperlink to: Protecting Indigenous values in water management: a challenge to conventional environmental flow assessments
. 

Fojut TL, Palumbo AJ and Tjeerdema RS (2012) Aquatic life water quality criteria derived via the UC 
Davis method: III. Diuron. In: Tjeerdema RS (ed) Aquatic life water quality criteria for 
selected pesticides. Reviews of Environmental Contamination and Toxicology, vol. 216. 
Springer, Boston, USA, 105–141. https://doi.org/10.1007/978-1-4614-2260-0_3. 


Friess DA, Yando ES, Abuchahla GM, Adams JB, Cannicci S, Canty SW, Cavanaugh KC, Connolly RM, 
Cormier N and Dahdouh-Guebas F (2020) Mangroves give cause for conservation optimism, 
for now. Current Biology 30(4), R153–R154. 

Fukuda Y and Cuff N (2013) Vegetation communities as nesting habitat for the saltwater crocodiles 
in the Northern Territory of Australia. Herpetological Conservation and Biology 8(3), 641–
651. 

Gao J, Wang F, Jiang W, Miao J, Wang P, Zhou Z and Liu D (2020) A full evaluation of chiral 
phenylpyrazole pesticide flufiprole and the metabolites to non-target organism in paddy 
field. Environmental Pollution, 264, 114808. DOI: 10.1016/j.envpol.2020.114808. 

Giglio A and Vommaro ML (2022) Dinitroaniline herbicides: a comprehensive review of toxicity and 
side effects on animal non-target organisms. Environmental Science and Pollution Research 
29(51), 76687–76711. DOI: 10.1007/s11356-022-23169-4. 

Grain Storage Extension Project (2024) Stored grain information hub. Viewed 29 February 2024, Hyperlink to: Stored grain information hub
. 

GRDC (2024) WeedSmart. Grains Research and Development Corporation. Viewed 20 March 2024, Hyperlink to: WeedSmart
. 

Guest MA, Connolly RM, Lee SY, Loneragan NR and Brietfuss MJ (2006) Mechanism for the small 
scale movement of carbon among estuarine habitats: organic matter transfer not crab 
movement. Oecologia 148(1), 88–96. 

Hafi A, Arthur T, Medina M, Warnakula C, Addai D and Stenekes N (2023) Cost of established pest 
animals and weeds to Australian agricultural producers. Australian Bureau of Agricultural 
and Resource Economics and Sciences. Viewed 5 February 2024, Hyperlink to: Cost of established pest animals and weeds to Australian agricultural producers
. 

Hansen B, Fuller R, Watkins D, Rogers D, Clemens R, Newman M, Woehler E and Weller D (2016) 
Revision of the East Asian–Australasian Flyway population estimates for 37 listed migratory 
shorebird species. BirdLife Australia, Melbourne. 

Hart BT, Lake PS, Webb JA and Grace MR (2003) Ecological risk to aquatic systems from salinity 
increases. Australian Journal of Botany 51(6), 689–702. 

Hassaan MA and El Nemr A (2020) Pesticides pollution: classifications, human health impact, 
extraction and treatment techniques. Egyptian Journal of Aquatic Research 46(3), 207–220. 
DOI: 10.1016/j.ejar.2020.08.007. 

Hennecke BR (2012) Assessing new Weeds of National Significance candidates. In: Proceedings of 
the 18th Australasian Weeds Conference. Weed Society of Victoria Inc., Melbourne, 191–194 
Viewed 20 March 2024, Hyperlink to: Assessing new Weeds of National Significance candidates
. 

Hermoso V, Ward DP and Kennard MJ (2013) Prioritizing refugia for freshwater biodiversity 
conservation in highly seasonal ecosystems. Diversity and Distributions 19(8), 1031–1042. Hyperlink to: Prioritizing refugia for freshwater biodiversity conservation in highly seasonal ecosystems
. 

Hughes J, Yang A, Marvanek S, Wang B, Gibbs M and Petheram C (2024a) River model calibration 
for the Victoria catchment. A technical report from the CSIRO Victoria River Water Resource 
Assessment for the National Water Grid. CSIRO, Australia. 


Hughes J, Yang A, Wang B, Marvanek S, Gibbs M and Petheram C (2024b) River model scenario 
analysis for the Victoria catchment. A technical report from the CSIRO Victoria River Water 
Resource Assessment for the National Water Grid. CSIRO, Australia. 

Irvin S, Coman G, Musson D and Doshi A (2018) Aquaculture viability. A technical report to the 
Australian Government from the CSIRO Northern Australia Water Resource Assessment, part 
of the National Water Infrastructure Development Fund: Water Resource Assessments. 
CSIRO, Australia. 

Irvin S, Coman G, Musson D, Doshi A and Stokes C (2018) Aquaculture viability. A technical report 
to the Australian Government from the CSIRO Northern Australia Water Resource 
Assessment, part of the National Water Infrastructure Development Fund: Water Resource 
Assessments. CSIRO, Australia. Viewed 14 February 2024, Hyperlink to: Aquaculture viability. A technical report to the Australian Government from the CSIRO Northern Australia Water Resource Assessment, part of the National Water Infrastructure Development Fund: Water Resource Assessments
. 

Jackson S, Finn M, Woodward E and Featherston P (2011) Indigenous socio-economic values and 
river flows: a summary of research results 2008–2010. CSIRO, Darwin. Hyperlink to: Indigenous socio-economic values and river flow: a summary of research results 2008–2010
. 

Jardine TD, Bond NR, Burford MA, Kennard MJ, Ward DP, Bayliss P, Davies PM, Douglas MM, 
Hamilton SK, Melack JM, Naiman RJ, Pettit NE, Pusey BJ, Warfe DM and Bunn SE (2015) Does 
flood rhythm drive ecosystem responses in tropical riverscapes? Ecology 96(3), 684–692. 

Jolly I, Taylor A, Rassam D, Knight J, Davies P and Harrington G (2013) Surface water — 
groundwater connectivity. . A technical report to the Australian Government from the CSIRO 
Flinders and Gilbert Agricultural Resource Assessment, part of the North Queensland 
Irrigated Agriculture Strategy. CSIRO Water for a Healthy Country and Sustainable 
Agriculture flagships, Australia. 

Kaur R, Mavi GK, Raghav S and Khan I (2019) Pesticides classification and its impact on 
environment. International Journal of Current Microbiology and Applied Science 8(3), 1889–
1897. 

Kearney M, Phillips BL, Tracy CR, Christian KA, Betts G and Porter WP (2008) Modelling species 
distributions without using species distributions: the cane toad in Australia under current 
and future climates. Ecography 31(4), 423–434. Hyperlink to: Modelling species distributions without using species distributions: the cane toad in Australia under current and future climate
. 

Kennard MJ, Mackay SJ, Pusey BJ, Olden JD and Marsh N (2010) Quantifying uncertainty in 
estimation of hydrologic metrics for ecohydrological studies. River Research and Applications 
26(2010), 137–156. 

Kirby SL and Faulks JJ (2004) Victoria River Catchment. An assessment of the physical and 
ecological condition of the Victoria River and its major tributaries. Northern Territory 
Government. Department of Infrastructure, Planning and Environment, Australia. Viewed 15 
October 2024, https://territorystories.nt.gov.au/10070/631075/0/80. 

Kozik R, Meissner W, Listewnik B, Nowicki J, Lasecki R (2022) Differences in foraging behaviour of a 
migrating shorebird at stopover sites on regulated and unregulated sections of a large 
European lowland river. J Ornithol 163, 791–802. https://doi.org/10.1007/s10336-022-
01984-3 


Kroon FJ, Thorburn P, Schaffelke B and Whitten S (2016) Towards protecting the Great Barrier Reef 
from land-based pollution. Global Change Biology 22, 1985–2002. DOI: 10.1111/gcb.13262. 

Kutt A, Felderhof L, VanDerWal J, Stone P and Perkins G (2009) Chapter 4. Terrestrial ecosystems 
of northern Australia. Northern Australia Land and Water Science Review, October 2009. 

Landos M, Calogeras C, Ruscoe J-A, Hayward S and Ruscoe J (2019) National biosecurity plan 
guidelines for Australian barramundi farms. Australian Government Department of 
Agriculture. Viewed 20 February 2024, 
https://www.agriculture.gov.au/sites/default/files/sitecollectiondocuments/agriculture-
food/nrs/2013-14-results/barramundi.pdf. 

Layman CA (2007) What can stable isotope ratios reveal about mangroves as fish habitat? Bulletin 
of Marine Science 80, 513–527. 

Le DP, Tran TT, Gregson A and Jackson R (2020) TEF1 sequence-based diversity of Fusarium species 
recovered from collar rot diseased cotton seedlings in New South Wales, Australia. 
Australasian Plant Pathology 49(3), 277–284. Hyperlink to: TEF1 sequence-based diversity of Fusarium species recovered from collar rot diseased cotton seedlings in New South Wales, Australia
. 

Leahy SM and Robins JB (2021) River flows affect the growth of a tropical finfish in the wet-dry 
rivers of northern Australia, with implications for water resource development. 
Hydrobiologia 848(18), 4311–4333. 

Leigh C and Sheldon F (2008) Hydrological changes and ecological impacts associated with water 
resource development in large floodplain rivers in the Australian tropics. River Research and 
Applications 24(2008), 1251–1270. 

Lewis SE, Brodie JE, Bainbridge ZT, Rohde KW, Davis AM, Masters BL, Maughan M, Devlin MJ, 
Mueller JF and Schaffelke B (2009) Herbicides: a new threat to the Great Barrier Reef. 
Environmental Pollution 157, 2470–2484. DOI: 10.1016/j.envpol.2009.03.006. 

Mainstone CP and Parr W (2002) Phosphorus in rivers — ecology and management. Science of the 
Total Environment 282–283, 25–47. DOI: 10.1016/S0048-9697(01)00937-8. 

Makinson RO, Pegg GS and Carnegie AJ (2020) Myrtle Rust in Australia – a National Action Plan. 
Australian Plant Biosecurity Science Foundation. Viewed 11 March 2024, Hyperlink to: Myrtle Rust in Australia – a National Action Plan
. 

Marsh N, Sheldon F, Wettin P, Taylor C and Barma D (2012) Guidance on ecological responses and 
hydrological modelling for low-flow water planning, March 2012. The National Water 
Commission, Canberra. 

Martens DA (2005) Denitrification. In: Hillel D and Hatfield JL (eds) Encyclopedia of soils in the 
environment (Vol. 3). Elsevier, 378–382. DOI: 10.1016/B0-12-348530-4/00138-7. 

McClenachan G, Witt M and Walters LJ (2021) Replacement of oyster reefs by mangroves: 
unexpected climate‐driven ecosystem shifts. Global Change Biology 27(6), 1226–1238. 

McJannet D, Marvanek S, Kinsey-Henderson A, Petheram C and Wallace J (2014) Persistence of in-
stream waterholes in ephemeral rivers of tropical northern Australia and potential impacts 
of climate change. Marine and Freshwater Research 65(12), 1131–1144. Hyperlink to: Persistence of in-stream waterholes in ephemeral rivers of tropical northern Australia and potential impacts of climate change
. 


McMahon TA and Finlayson BL (2003) Droughts and anti-droughts: the low flow hydrology of 
Australian rivers. Freshwater Biology 48(2003), 1147–1160. 

Meynecke J, Lee S, Grubert M, Brown I, Montgomery S, Gribble N, Johnston D and Gillson J (2010) 
Evaluating the environmental drivers of mud crab (Scylla serrata) catches in Australia. Final 
Report FRDC 2008/012. The Fisheries Research and Development Corporation and Griffith 
University, Queensland. Viewed 11 March 2024, 
https://www.frdc.com.au/sites/default/files/products/2008-012-DLD.pdf. 

Miller JL, Schmidt TS, Van Metre PC, Mahler BJ, Sandstrom MW, Nowell LH, Carlisle DM and 
Moran PW (2020) Common insecticide disrupts aquatic communities: A mesocosm-to-field 
ecological risk assessment of fipronil and its degradates in U.S. streams. Science Advances 
6(43), eabc1299. DOI: 10.1126/sciadv.abc1299. 

Milton D, Yarrao M, Fry G and Tenakanai C (2005) Response of barramundi, Lates calcarifer, 
populations in the Fly River, Papua New Guinea to mining, fishing and climate-related 
perturbation. Marine and Freshwater Research 56(7), 969–981. 

Mitchell A, Reghenzani J, Faithful J, Furnas M and Brodie J (2009) Relationships between land use 
and nutrient concentrations in streams draining a wet-tropics catchment in northern 
Australia. Marine and Freshwater Research 60, 1097–1108. DOI: 10.1071/MF08330. 

Mohanty SS and Jena HM (2019) A systemic assessment of the environmental impacts and 
remediation strategies for chloroacetanilide herbicides. Journal of Water Process 
Engineering 31, 100860. DOI: 10.1016/j.jwpe.2019.100860. 

Mohd-Azlan J, Noske RA and Lawes MJ (2012) Avian species-assemblage structure and indicator 
bird species of mangroves in the Australian monsoon tropics Emu – Austral Ornithology 
112(4), 287–297. 

Moore GA, Munday C and Barua P (2022) Environmental weed risk assessment protocol for 
growing non-indigenous plants in the Western Australian rangelands. WA Government 
Department of Primary Industries and Regional Development. Viewed 20 March 2024, Hyperlink to: Environmental weed risk assessment protocol for growing non-indigenous plants in the Western Australian rangelands
. 

Mosley LM and Fleming N (2010) Pollutant loads returned to the Lower Murray River from flood-
irrigated agriculture. Water, Air, and Soil Pollution 211(1–4), 475–487. DOI: 10.1007/s11270-
009-0316-1. 

Motson K, Mishra A and Waltham N (2024) A review of water quality studies relevant to northern 
Australia. A technical report from the CSIRO Victoria and Southern Gulf Water Resource 
Assessments for the National Water Grid. CSIRO, Australia. 

Moulden JH, Yeates SJ, Strickland GR and Plunkett GM (2006) Developing an environmentally 
responsible irrigation system for cotton in the Ord River Irrigation Area. Proceedings of 
ANCID 2006, 16–19 October, Darwin, NT. The Australian National Committee on Irrigation 
and Drainage, Sydney. 

myBMP (2024) myBMP. Viewed 26 February 2024, Hyperlink to: myBMP
. 

Naccarato A, Vommaro ML, Amico D, Sprovieri F, Pirrone N, Tagarelli A and Giglio A (2023) Triazine 
herbicide and NPK fertilizer exposure: accumulation of heavy metals and rare earth 


elements, effects on cuticle melanization, and immunocompetence in the model species 
Tenebrio molitor. Toxics 11(6), 499. 

Naughton JM, O’Dea K and Sinclair AJ (1986) Animal foods in traditional Australian aboriginal diets: 
polyunsaturated and low in fat. Lipids 21(11), 684–690. 

Ndehedehe CE, Burford MA, Stewart-Koster B and Bunn SE (2020) Satellite-derived changes in 
floodplain productivity and freshwater habitats in northern Australia (1991–2019). Ecological 
Indicators 114, 106320. 

Ndehedehe CE, Onojeghuo AO, Stewart-Koster B, Bunn SE and Ferreira VG (2021) Upstream flows 
drive the productivity of floodplain ecosystems in tropical Queensland. Ecological Indicators 
125, 107546. 

Nielsen D, Merrin L, Pollino C, Karim F, Stratford D and O’Sullivan J (2020) Climate change and dam 
development: effects on wetland connectivity and ecological habitat in tropical wetlands. 
Ecohydrology 2020, 13pgs. Hyperlink to: Climate change and dam development: effects on wetland connectivity and ecological habitat in tropical wetlands
. 

Nilsson C and Berggren K (2000) Alterations of riparian ecosystems caused by river regulation. 
BioScience 50(9), 783–792. 

NT Farmers (2022) Northern Australia broadacre cropping manual. Northern Territory Farmers 
Association. Viewed 4 July 2024, Hyperlink to: Northern Australia broadacre cropping manual
. 

NT Government (2014) Field guide to pests, beneficials, diseases and disorders of vegetables in 
northern Australia. NT Government Department of Primary Industry and Fisheries. Viewed 
20 March 2024, Hyperlink to: Field guide to pests, beneficials, diseases and disorders of vegetables in northern Australia
. 

NT Government (2016) Northern Territory Biosecurity Strategy 2016–2026. Viewed 30 January 
2024, Hyperlink to: Northern Territory Biosecurity Strategy 2016-2026
. 

NT Government (2021) Katherine Regional Weeds Strategy 2021–2026. NT Government 
Department of Environment, Parks and Water Security. Viewed 2 January 2024, Hyperlink to: Katherine Regional Weeds Strategy 2021-2026
. 

NT Government (2023) Northern Territory plant health manual. Viewed 14 February 2024, Hyperlink to: Northern Territory plant health manual
. 

NT Government (2024a) Plant diseases and pests. Viewed 27 February 2024, Hyperlink to: Plant diseases and pests
. 

NT Government (2024b) Cucumber green mottle mosaic virus. Viewed 19 February 2024, Hyperlink to: Cucumber green mottle mosaic virus
. 


NT Government (2024c) Using chemicals responsibly. Viewed 26 February 2024, Hyperlink to: Using chemicals responsibly
. 

NT Government (2024d) Feral animals. Viewed 27 February 2024, Hyperlink to: Feral animals
. 

Olden JD and Poff L (2003) Redundancy and the choice of hydrologic indices for characterizing 
streamflow regimes. River Research and Applications 19(2003), 101–121. 

Outbreak (2023a) Red imported fire ant (Solenopsis invicta), Outbreak Animal and Plant Pests and 
Diseases website. Viewed 10 March 2024, Hyperlink to: Red imported fire ant (Solenopsis invicta)
. 

Outbreak (2023b) Banana freckle (Phyllosticta cavendishii). Outbreak Animal and Plant Pests and 
Diseases website. Viewed 20 March 2024, Hyperlink to: Banana freckle (Phyllosticta cavendishii)
. 

Outbreak (2024) Respond to, prevent and prepare for animal and plant pest and disease 
outbreaks. Outbreak Animal and Plant Pests and Diseases website. Viewed 23 February 
2024, https://www.outbreak.gov.au/. 

Owers CJ, Woodroffe CD, Mazumder D and Rogers K (2022) Carbon storage in coastal wetlands is 
related to elevation and how it changes over time. Estuarine, Coastal and Shelf Science, 
107775. 

Palviainen M, Peltomaa E, Laurén A, Kinnunen N, Ojala A, Berninger F, Zhu X and Pumpanen J 
(2022) Water quality and the biodegradability of dissolved organic carbon in drained boreal 
peatland under different forest harvesting intensities. Science of the Total Environment 806, 
150919. DOI: 10.1016/j.scitotenv.2021.150919. 

Pelicice FM, Pompeu PS and Agostinho AA (2015) Large reservoirs as ecological barriers to 
downstream movements of neotropical migratory fish. Fish and Fisheries 2015(16), 697–715. 

Pettit NE, Bayliss P, Davies PM, Hamilton SK, Warfe DM, Bunn SE and Douglas MM (2011) Seasonal 
contrasts in carbon resources and ecological processes on a tropical floodplain. Freshwater 
Biology 56(6), 1047–1064. Hyperlink to Seasonal contrasts in carbon resources and ecological processes on a tropical floodplain 


PHA (2020) Fall Armyworm Continuity Plan for the Australian Grains Industry. Version 1, 
November 2020. Plant Health Australia. Viewed 2 January 2024, Hyperlink to: Fall Armyworm Continuity Plan for the Australian grains industry
. 

PHA (2021) Exotic pest identification and surveillance guide for tropical horticulture. Version 1.0, 
February 2021. Plant Health Australia. Viewed 30 September 2024, 
https://www.planthealthaustralia.com.au/wp-content/uploads/2023/12/Pest-Identification-
and-Surveillance-Guide-for-Tropical-Horticulture-18.8.21.pdf. 

PHA (2022) PLANTPLAN: Australian Emergency Plant Pest Response Plan. 13 December 2022. Plant 
Health Australia. Viewed 30 September 2024, https://www.planthealthaustralia.com.au/wp-
content/uploads/2024/09/EPPRD-23-September-2024.pdf. 


PHA (2024a) Industry programs. Plant Health Australia. Viewed 30 September2024, Hyperlink to: Industry programs
. 

PHA (2024b) Protecting grains from diseases, pests and weeds. Plant Health Australia. Grains farm 
biosecurity program website. Viewed 30 September2024, Hyperlink to: Protecting grains from diseases, pests and weeds
. 

Piersma T & Baker A J (2000) Life history characteristics and the conservation of migratory 
shorebirds. In L. M. Gosling, & W. J. Sutherland (Eds.), Behaviour and conservation (pp. 105-
124). (Conservation Biology Series; Vol. 2). Cambridge University Press. 

PIRSA (2024) Plant Quarantine Standard South Australia. Version 17.5. SA Government 
Department of Primary Industries and Regions. Viewed 30 April 2024, Hyperlink to: Plant Quarantine Standard South Australia
. 

Plagányi É, Kenyon R, Blamey L, Robins J, Burford M, Pillans R, Hutton T, Hughes J, Kim S and Deng 
RA (2024) Integrated assessment of river development on downstream marine fisheries and 
ecosystems. Nature Sustainability 7(1), 31–44. 

Poff NL, Olden JD, Merritt DM and Pepin DM (2007) Homogenization of regional river dynamics by 
dams and global biodiversity implications. Proceedings of the National Academy of Sciences 
104(4), 5732–5737. 

Pollino C, Barber E, Buckworth R, Cadiegues M, Deng R, Ebner B, Kenyon R, Liedloff A, Merrin L, 
Moeseneder C, Morgan D, Nielsen D, O'Sullivan J, Ponce Reyes R, Robson B, Stratford D, 
Stewart-Koster B and Turschwell M (2018) Synthesis of knowledge to support the 
assessment of impacts of water resource development to ecological assets in northern 
Australia: asset analysis. A technical report to the Australian Government from the CSIRO 
Northern Australia Water Resource Assessment, part of the National Water Infrastructure 
Development Fund: Water Resource Assessments. CSIRO, Canberra. 

Pyšek P, Hulme PE, Simberloff D, Bacher S, Blackburn TM, Carlton JT, Dawson W, Essl F, Foxcroft 
LC, Genovesi P, Jeschke JM, Kühn I, Liebhold AM, Mandrak NE, Meyerson LA, Pauchard A, 
Pergl J, Roy HE, Seebens H, van Kleunen M, Vilà M, Wingfield MJ and Richardson DM (2020) 
Scientists’ warning on invasive alien species. Biological Reviews 2020(95), 1511–1534. Hyperlink to: Scientists' warning on invasive alien species
. 

Queensland Government (2023) Your legal obligation for invasive freshwater animals. Queensland 
Government Department of Agriculture and Fisheries. Viewed 7 February 2024, Hyperlink to: Your legal obligation for invasive freshwater animals
. 

Rad SM, Ray AK and Barghi S (2022) Water pollution and agriculture pesticide. Clean Technologies 
4(4), 1088–1102. 

Records RM, Wohl E and Arabi M (2016) Phosphorus in the river corridor. Earth-Science Reviews 
158, 65–88. DOI: 10.1016/j.earscirev.2016.04.010. 

Roberts BH, Morrongiello JR, King AJ, Morgan DL, Saunders TM, Woodhead J and Crook DA (2019) 
Migration to freshwater increases growth rates in a facultatively catadromous tropical fish. 
Oecologia 191(2), 253–260. 


Roberts BH, Morrongiello JR, Morgan DL, King AJ, Saunders TM, Banks SC and Crook DA (2023) 
Monsoonal wet season influences the migration tendency of a catadromous fish 
(barramundi Lates calcarifer). Journal of Animal Ecology 93(1), 83–94. 

Robertson AI and Duke NC (1990) Mangrove fish-communities in tropical Queensland, Australia: 
spatial and temporal patterns in densities, biomass and community structure. Marine 
Biology 104, 369–379. 

Russell D and Garrett R (1983) Use by juvenile barramundi, Lates calcarifer (Bloch), and other 
fishes of temporary supralittoral habitats in a tropical estuary in northern Australia. Marine 
and Freshwater Research 34(5), 805–811. 

Russell D and Garrett R (1985) Early life history of barramundi, Lates calcarifer (Bloch), in north-
eastern Queensland. Marine and Freshwater Research 36(2), 191–201. 

Schmutz S and Sendzimir J (eds) (2018) Riverine ecosystem management science for governing 
towards a sustainable future. Springer Open. https://doi.org/10.1007/978-3-319-73250-3. 

Schofield KA, Alexander LC, Ridley CE, Vanderhoof MK, Fritz KM, Autrey BC, DeMeester JE, Kepner 
WG, Lane CR, Leibowitz SG and Pollard AI (2018) Biota connect aquatic habitats throughout 
freshwater ecosystem mosaics. Journal of the American Water Resources Association 54(2), 
372–399. 

Setterfield SA, Rossiter-Rachor NA, Douglas MM, Wainger L, Petty AM, Barrow P, Shepherd IJ and 
Ferdinands KB (2013) Adding fuel to the fire: the impacts of non-native grass invasion on fire 
management at a regional scale. PLoS ONE, 8(5), e59144. Hyperlink to: Adding fuel to the fire: the impacts of non-native grass invasion on fire management at a regional scale
. 

Skhiri A and Dechmi F (2012) Impact of sprinkler irrigation management on the Del Reguero river 
(Spain) II: phosphorus mass balance. Agricultural Water Management 103, 130–139. 
DOI: 10.1016/j.agwat.2011.11.004. 

Skilleter GA, Olds A, Loneragan NR and Zharikov Y (2005) The value of patches of intertidal 
seagrass to prawns depends on their proximity to mangroves. Marine Biology 147, 353–365. 

Stratford D, Kenyon R, Pritchard J, Merrin L, Linke S, Ponce Reyes R, Buckworth R, Castellazzi P, 
Costin B, Deng R, Gannon R, Gao S, Gilbey S, Lachish S, McGinness H and Waltham N (2024a) 
Ecological assets of the Victoria catchment to inform water resource assessments. A 
technical report from the CSIRO Victoria River Water Resource Assessment for the National 
Water Grid. CSIRO, Australia. 

Stratford D, Linke S, Merrin L, Kenyon R, Ponce Reyes R, Buckworth R, Deng RA, Hughes J, 
McGinness H, Pritchard J, Seo L and Waltham N (2024b) Assessment of the potential 
ecological outcomes of water resource development in the Victoria catchment. A technical 
report from the CSIRO Victoria River Water Resource Assessment for the National Water 
Grid. CSIRO, Australia. 

Stratford D, Merrin L, Linke S, Kenyon R, Ponce Reyes R, Buckworth R, Deng RA, McGinness H, 
Pritchard J, Seo L and Waltham N (2024c) Assessment of the potential ecological outcomes 
of water resource development in the Roper catchment. A technical report from the CSIRO 
Roper River Water Resource Assessment for the National Water Grid. CSIRO, Australia. 


Subcommittee on Domestic Quarantine and Market Access (2024) Moving plant goods interstate. 
Australian Interstate Quarantine website. Viewed 28 March 2024, Hyperlink to: Moving plant goods interstate
. 

Tanimoto M, Robins JB, O’Neill MF, Halliday IA and Campbell AB (2012) Quantifying the effects of 
climate change and water abstraction on a population of barramundi (Lates calcarifer), a 
diadromous estuarine finfish. Marine and Freshwater Research 63(8), 715–726. 

Tanji KK and Kielen NC (2002) Agricultural water management in arid and semi-arid areas. 
Irrigation and drainage paper 61. Food and Agriculture Organization of the United Nations, 
Rome. 

Thimdee W, Deein G, Sangrungruang C and Matsunaga K (2001) Stable carbon and nitrogen 
isotopes of mangrove crabs and their food sources in a mangrove fringed estuary in 
Thailand. Benthos Research 56, 73–80. 

Thorburn PJ, Wilkinson SN and Silburn DM (2013) Water quality in agricultural lands draining to 
the Great Barrier Reef: a review of causes, management and priorities. Agriculture, 
Ecosystems and Environment 180, 4–20. DOI: 10.1016/j.agee.2013.07.006. 

Tickell SJ (1994) Dryland salinity hazard mapping Northern Territory [online]. In: Water Down 
Under 94: Groundwater Papers. Preprints of papers. National conference publication 
(Institution of Engineers, Australia), no. 94/14. Institution of Engineers, Australia, Barton, 
ACT, 745–748. 

Tockner K, Pusch M, Borchardt D and Lorang MS (2010) Multiple stressors in coupled river–
floodplain ecosystems. Freshwater Biology 55, 135–151. 

U.S. EPA (2024) Causal Analysis/Diagnosis Decision Information System (CADDIS): pH. United 
States Environmental Protection Agency. Viewed 8 September 2024, 
https://www.epa.gov/caddis/ph. 

van de Pol, M, Bailey, LD, Frauendorf, M, Allen, AM, van der Sluijs, M, Hijner, N, Brouwer, L, de 
Kroon, H, Jongejans E, Ens, BJ. (2024) Sea-level rise causes shorebird population collapse 
before habitats drown. Nat. Clim. Chang. 14, 839–844. https://doi.org/10.1038/s41558-024-
02051-w 

Waltham N, Burrows D, Butler B, Wallace J, Thomas C, James C and Brodie J (2013) Waterhole 
ecology in the Flinders and Gilbert catchments. A technical report to the Australian 
Government from the CSIRO Flinders and Gilbert Agricultural Resource Assessment, part of 
the North Queensland Irrigated Agriculture Strategy. CSIRO Water for a Healthy Country and 
Sustainable Agriculture flagships, Australia. 

Wang YYL, Xiong J, Ohore OE, Cai Y-E, Fan H, Sanganyado E, Li P, You J, Liu W and Wang Z (2022) 
Deriving freshwater guideline values for neonicotinoid insecticides: Implications for water 
quality guidelines and ecological risk assessment. Science of the Total Environment 828, 
154569. DOI: 10.1016/j.scitotenv.2022.154569. 

Ward M, Carwardine J, Yong CJ, Watson JEM, Silcock J, Taylor GS, Lintermans M, Gillespie GR, 
Garnett ST, Woinarski J, Tingley R, Fensham RJ, Hoskin CJ, Hines HB, Roberts JD, Kennard MJ, 
Harvey MS, Chapple DG and Reside AE (2021) A national‐scale dataset for threats impacting 


Australia’s imperiled flora and fauna. Ecology and Evolution 11(17), 11749–11761. 

Waterhouse J, Brodie J, Lewis S and Mitchell A (2012) Quantifying the sources of pollutants in the 
Great Barrier Reef catchments and the relative risk to reef ecosystems. Marine Pollution 
Bulletin 65, 394–406. DOI: 10.1016/j.marpolbul.2011.09.031. 

West AD, Goss-Custard JD, dit Durell SE, Stillman RA (2005) Maintaining estuary quality for 
shorebirds: towards simple guidelines. Biological Conservation 123(2), 211-224. 

Yang A, Petheram C, Marvanek S, Baynes F, Rogers L, Ponce Reyes R, Zund P, Seo L, Hughes J, 
Gibbs M, Wilson PR, Philip S and Barber M (2024) Assessment of surface water storage 
options in the Victoria and Southern Gulf catchments. A technical report from the CSIRO 
Victoria River and Southern Gulf Water Resource Assessments for the National Water Grid. 
CSIRO Australia. 

Yeates S (2016) Comparison of delayed release N fertiliser options for cotton on clay soils with 
urea; yield, N fertiliser uptake and N losses in runoff – Burdekin 2013–2015. Cotton Research 
and Development Project: CSP1302. Viewed 8 September 2024, 
https://www.insidecotton.com/sites/default/files/article-files/CSP1302_Final_Report.pdf.