Monitoring, evaluation and research
Brolga at Toorale.
Photo: Lachlan Copeland
Monitoring and evaluating the use of water for the environment is helping to build knowledge about the best way to improve the health of the rivers and wetlands of the Basin.
The Commonwealth Environmental Water Office (CEWO) works with Basin states, the Murray-Darling Basin Authority, scientists and the local community to build this knowledge.
There are a number of programs currently underway in the Northern Intersecting Streams.
Some recent examples of learnings include:
- Commonwealth water for the environment contributes to the breeding and recruitment of native fish species (e.g. golden perch) in the Warrego system. Golden perch recruits from the Warrego are likely to be contributing to the wider population in the Darling River system.
- The fish community in the Warrego River are highly resilient and can survive highly variable flow conditions, including drying down. They are then able to recolonise and recruit on the larger flows.
- Supporting the main waterholes on the Warrego is important for providing source populations of native fish and providing refugia for waterbirds.
- Using water for the environment to inundate parts of the Western Floodplain increases productivity that support the highest abundance and diversity of frogs, invertebrates and waterbirds. It also increases the cover and richness of vegetation.
Juvenile golden perch sampled in Booka Western bywash, May 2019. Photo: Eco Logical Australia
- Lagoons in the Queensland Lower Balonne are known to provide important habitat for a range of native fish species including golden perch, Australian smelt, spangled perch, bony bream, olive perchlet and Hyrtl’s tandan.
- Monitoring has shown that prolonged drought has reduced the condition of all vegetation community types at the Narran Lakes (Dharriwaa), with river red gum being the most affected tree species.
- Despite significant dieback at the Narran Lakes, lignum has been shown to resprout in response to rainfall and may still provide suitable nesting habitat for waterbirds following inundation. The final report for this monitoring project is at: Vegetation Community and Tree Stand Condition Assessment of the Flood-Dependent Vegetation of Narran Lakes Nature Reserve (Dharriwaa) (2020-2021) .
- A pilot project in 2020 demonstrated that additional water can be provided to the Narran Lakes via reimbursement to water-licence holders that refrain from pumping water they are legally entitled to take. This project meant that more water from the Lower Balonne remained in the river and reached the Narran Lakes, helping to revive some critical waterbird habitat.
- After wetter conditions from early 2020 onwards, waterbirds bred at the Narran Lakes from January to April 2022. This is the first time that colonial waterbirds have bred at at that site in a decade, and the first time in more than 20 years that there has been waterbird breeding at Macquarie Marshes, Gwydir Wetlands and the Narran Lakes at the same time. Around 10,000 straw-necked ibis nests were detected in two colonies, with other species including royal and yellow-billed spoonbills and egrets also recorded as nesting. For more information on 2021-22 Narran Lakes waterbird breeding, please see: Final Report June 2022 - Dharriwaa-Narran Lakes Nature Reserve Colonial Waterbird Reproductive Success Monitoring 2022.
- The Commonwealth Environmental Water Office also invested in waterbird satellite tagging to track how birds move in the landscape at the Narran Lakes and other sites in the Murray-Darling Basin. More information on waterbird tracking can be found at: Satellite tracking.
- Connectivity between the Barwon-Darling and its tributaries can be enhanced using water for the environment, which is important for supporting native fish movement.
- Commonwealth water for the environment delivered as part of natural flow events can improve water quality, nutrient cycling and provide access to habitat for aquatic species.
- Extended dry periods and cease to flow conditions results in significant loss of freshwater mussels in the Barwon-Darling and its tributaries. The provision and protection of minimum baseflows is vital to their recovery and persistence.
- Delivering water for the environment through channels that are already wet minimises water quality issues. The water needed to replenish waterholes and allow for seepage is also much greater in rivers that have ceased to flow compared to still flowing rivers.
- The protection of water for the environment in the Barwon-Darling is very important for achieving the environmental outcomes targeted.
CEWO MER Program
The CEWO Monitoring, Evaluation and Research (MER) (Flow-MER) Program integrates and replaces monitoring and research activities under the Long-Term Intervention Monitoring (LTIM) and Environmental Water Knowledge and Research (EWKR) projects.
A detailed MER Plan has been developed for the Warrego-Darling MER Selected Area which sets out the schedule of activities to be undertaken in the Warrego-Darling to June 2022. The MER Warrego-Darling Selected Area project has been extended for a further twelve months.
CEWO Short Term Intervention Monitoring
The CEWO has funded monitoring activities to evaluate the short-term (annual) environmental response of selected watering actions in the northern unregulated rivers. Final reports can be found in the table below.
Monitoring, Evaluation and Research Activities and Reports
|Link to report||Description||Date||Link to relevant program|
|Junction of the Warrego and Darling rivers Selected Area 2021-22 Annual Summary Report||This report presents the monitoring and evaluation results from the third year of the Monitoring, Evaluation and Research project at the Junction of the Warrego and Darling rivers.||2021-222||MER
|Vegetation Community and Tree Stand Condition Assessment of the Flood-Dependent Vegetation of Narran Lakes Nature Reserve (Dharriwaa) (2020-2021 )||Report on response of native vegetation to flows and drought at the Narran Lakes (Dharriwaa) in the Lower Balonne from 2020 to 2021. The report was completed by the University of New England in collaboration with 2Rog Consulting, members of the Narran Joint Management Committee, NSW Department of Planning and Environment and NSW National Parks and Wildlife Service.||2022||STIM|
|Final Report June 2022 - Dharriwaa-Narran Lakes Nature Reserve Colonial Waterbird Reproductive Success Monitoring 2022||Report on outcomes of waterbird breeding at Narran Lakes (Dharriwaa) in 2021-22. The report was prepared by the University of New South Wales Centre for Ecosystem Science, with input from NSW Department of Planning and Environment and NSW National Parks and Wildlife Service.||2022||STIM|
|Junction of the Warrego and Darling rivers Selected Area 2020-21 Annual Summary Report||This report presents the monitoring and evaluation results from the second year of the Monitoring, Evaluation and Research project at the Junction of the Warrego and Darling rivers.||2020-21||MER
|Desiccation tolerance of river and floodplain mussels in the Murray–Darling Basin||Report on the desiccation tolerance of River Mussel and the Floodplain Mussel under different temperatures. This research was undertaken by NSW DPI Fisheries in collaboration with Murdoch University.||2022||STIM|
|Habitat and flow requirements of freshwater mussels in the Northern Murray–Darling Basin||Report on the monitoring of freshwater mussels undertaken by Griffith University, to understand the impact of the 2017–2020 drought.||2020||STIM|
|Junction of the Warrego and Darling rivers Selected Area 2019-20 Annual Summary Report||This report presents the monitoring and evaluation results from the first year of the Monitoring, Evaluation and Research project at the Junction of the Warrego and Darling rivers.||2019-20||MER
|Warrego-Darling MER Project Newsletters||Newsletters detailing recent monitoring activities, ecological observations and findings, and case studies.||2019-current||MER
|Junction of the Warrego and Darling Rivers Selected Area Five Year Evaluation Report and Appendices||Warrego-Darling River system monitoring and evaluation report||2019||LTIM|
|Report onto the Warrego River flow into the Darling: April - June 2019||Warrego-Darling River system monitoring and evaluation report||2019||LTIM|
|MER Program: Junction of the Warrego and Darling Rivers Selected Area Monitoring, Evaluation and Research Plan (2019-2022)||Schedule of monitoring, evaluation and research activities to be undertaken in the Warrego-Darling river systems June 2019 – June 2022||2019||MER
|LTIM Project Junction of the Warrego and Darling rivers Selected Area – 2017-18 Evaluation Report||Warrego-Darling river system monitoring and evaluation report||2017‑18||LTIM|
|LTIM Project junction of the Warrego and Darling rivers Selected Area; Annual Evaluation Report 2016-17||Warrego-Darling river system monitoring and evaluation report||2016-17||LTIM|
|LTIM Project junction of the Warrego and Darling rivers Selected Area 2015-16 Evaluation Report||Warrego-Darling river system monitoring and evaluation report||2015-16||LTIM|
|LTIM Project junction of the Warrego and Darling rivers Selected Area; Annual Evaluation Report||Warrego-Darling river system monitoring and evaluation report||2014-15||LTIM|
|LTIM Project Junction of the Warrego and Darling Rivers Selected Area||Schedule of on-ground monitoring and evaluation activities in the Edward Wakool 2014-2019||2014||LTIM|
|Aquatic fauna use of the Warrego River Western Floodplain summer 2017||Report on aquatic fauna use of the Toorale Western Floodplain in summer 2017 following significant rainfall and inundation of the site winter/spring 2016||2017||LTIM|
Research was conducted in the Lower Balonne (including Narran Lakes), including:
|Fish monitoring and assessment of habitat condition in the Barwon-Darling (Northern Connectivity Event)||Fish monitoring (including movement) by NSW DPI Fisheries to assess fish response to the Northern Connectivity event (autumn 2018). Fish were monitored at nine sites between Bourke and Menindee, involving electrofishing and bait traps to cover the whole fish community, including larger fish and smaller fish. A fine-scale acoustic array was also set up between Louth and Tilpa and radio-tags surgically inserted into 48 golden perch. During that flow, several of these fish moved over 5 kilometres in a single day. Over the flow event of around a month, most fish moved tens of kilometres. Some moved upstream to weirs which blocked their progress.||2018||STIM|
|A comparative assessment of event-based mechanisms for providing water to the Narran Lakes||Report investigating a range of options and opportunities for event-based mechanisms to enhance flows to the Narran Lakes by up to 10 GL to help meet its environmental water requirements.||2017||STIM|
|Barwon-Darling: low flow environmental watering impediments and opportunities||Report investigating the impact that current water management arrangements have on achieving environmental outcomes under low flow conditions in the Barwon-Darling and potential options to address those impacts.||2017||STIM|
|Characterising the ecological effects of changes in the ‘low-flow hydrology’ of the Barwon-Darling River||Report describing how changes in the low flow hydrology associated with water resource development and river regulation impact on the health and function of the Barwon-Darling.||2017||STIM|
|Hydrological impacts of water management arrangements on low flows in the Barwon Darling River system||Report investigating the potential hydrological impacts of water management arrangements on low flows in the Barwon-Darling River.||2017||STIM|