The importance of this Recovery Reach
The Lower Darling River is significant for native fish in the Murray-Darling Basin. Iconic species such as Golden perch, Murray cod, Silver perch and Freshwater catfish, as well as a number of important small-bodied native fish species, live in this special river. The Darling River supports the breeding and recruitment (growth and survival) of fish, with Golden perch adults, for example, spawning upstream so that larvae and young fish drift downstream. As they drift they grow, so by the time they reach the Menindee Lakes, there are juveniles and adults able to repopulate, both in an upstream and downstream direction. Recent science demonstrates that Golden perch in the Murray system (from Echuca down to the Lower Lakes in South Australia) are often those that began life in the Darling River.
The Lower Darling River Murray cod population is particularly important for the recovery of adjacent populations in the mid and lower Murray River system that in recent years, have suffered severe declines with blackwater fish deaths across thousands of river kilometres.
Recovering the Lower Darling
NSW Department of Primary Industry, in collaboration with other State and Commonwealth agencies and organisations, are implementing management actions to protect and recover native fish populations. These actions include:
- Water quality monitoring to inform real time water management an minimise risk to fish stocks
- Identification and mapping of refuge pools to focus conservation and recovery actions
- Creation of artificially aerated refuge areas in the Lower Darling during periods of no flow
- Relocation of fish from diminishing pools to better quality waterbodies
- Mapping of key habitat types (snags, river benches) to inform delivery of flows through the Lower Baaka-Darling and ensure best outcomes with limited water volumes
- Community engagement and capacity building regarding water management and ecological recovery following the fish kills
- Fish community monitoring to track recovery of local fish stocks and highlight potential risks.
- Progress implementation of fish passage strategies to ensure fish can move to where they want to be!
What has been done
- Restocking – So far NSW Fisheries have released Murray cod and Golden perch fingerlings bred from adults that were ‘rescued’ from a drying lower Baaka-Darling, and relocated to the Narrandera Hatchery back in 2019. Local Barkandji representatives, school students, collaborating landowners, TO’s and local community representatives were invited to the re-stocking events at Pooncarie and Menindee (December 2020 and March 2021). Silver perch fingerlings are expected to be restocked back in to the Lower Baaka-Darling later inn 2021.
- Barkandji River Rangers Water Quality Monitoring – We are working with the Menindee-based Barkandji River Rangers to monitor water quality (particularly risk of hypoxia) as inflows reach Menindee through 2021. The rangers will then assist with monitoring water quality downstream of Menindee during subsequent releases to the Lower Baaka-Darling, to manage potential risks to fish.
- Environmental fish flow delivery and monitoring in the Lower Darling in spring-summer 2020/21 and now again for later in 2021. Our efforts aim to ensure interested community members are engaged in the planning of environmental flows to improve stakeholder understanding of environmental objectives and outcomes. In doing so we hope to also consider social or cultural concerns regarding environmental flow deliveries.
- Contribution to development and planning for a potential Menindee Hatchery. We provide ongoing support and technical advice to the steering committee exploring opportunities for a fish hatchery or grow out facility in Menindee.
- Fish in schools program – we have secured aquariums for Menindee/Pooncarie primary schools, and awaiting native Rainbowfish to house in them which the students will nurture.
- Fisheries have conducted several rounds of community sampling within the Lower Baaka-Darling including the Menindee Weir pool. The primary objectives of this sampling are to document the status of the remnant fish populations, and; track any recovery in subsequent years. Preliminary analyses indicate a positive short-term change in the fish community after the fish death events as flows returned to the region.
- Fish flow outcomes to date:
- Good spawning by surviving Lower Baaka Murray Cod in spring 2020 with evidence of subsequent recruitment (survival past vulnerable juvenile stages). This is great as natural breeding is by far the most effective way to recover Murray cod stocks in flowing rivers.
- We’ve also detected dispersal of juvenile Golden perch from northern basin spawning events through to the Menindee Lakes, with some passing further to the Lower Baaka-Darling in the environmental releases. in 2020 and again in 2021. Again, these breeding and dispersal events, supported by informed flow delivery, are the best way for us to initiate recovery of decimated lower Baaka-Darling fish populations.
- Increasing restocking efforts
- Improving fish passage through the region
- Rehabilitating aquatic habitat at priority reaches of the river
- Working with other state and federal agencies
- Engaging and building capacity with local communities, to deliver further management actions to support the movement, breeding and recruitment of native fish
Working with community:
There will be a number of activities with key stakeholders relationships in the Lower Darling region to provide on-ground coordination and information sharing across fisheries-related activities:
Iain had an information stand in conjunction with the MDBA and DPI Fisheries Fish Care at the Pooncarie “Ballads on the Baaka” (in March 2021). May have even played a few songs!
A community workshop was held in Menindee in late November 2019 to kick off on-ground engagement. It is hoped that more events like this one will provide a channel for more effective public engagement and local knowledge to be incorporated into research activities. It will also assist researchers and managers to dispel misinformation associated with particular topics and addressing wider community issues/concerns.
A citizen science project involving local people, including anglers and Aboriginal community members, will enable changes in the fish community to be tracked through time by locals. This will need cross-collaboration between researchers and scientists, which should boost understanding of fish and flow relationships, as well as ecological processes such as hydraulic variability, thermal stratification and oxygen depletion (linking to our aeration efforts to mitigate hypoxia in 2019-20).
Training in the use of monitoring equipment and data collection through photo-point monitoring will be provided so that community members can create photo point time series, or use photo diaries to document changes in their river, ideally pre and post drought recovery. Water quality units will also be made available for use by community members so that water quality data relating to assessing the effectiveness of aeration units Fisheries and the MDBA have installed in 2019-20 can be gathered.
A Recreational Fishing Database for the Lower Darling will be established so that anglers can contribute historic and contemporary catch records to inform our understanding of fish populations over time. This will involve the handing out of catch record sheets for completion by recreational fisherman, with data then sent to Fisheries officers for inclusion in the database. Simple results from period data interrogation will be disseminated back to the anglers themselves.
A “Fish, Flows and Cultural outcomes for the Lower Darling River “program will also be established so that Aboriginal voices are heard in water management activities and decision making. This will involve working with local Barkindji representatives so that they can inform future water management activities and decision making. This program is intended to align with the development of a “Healthy Country Program” by the Barkandji Native Title Group Aboriginal Corporation.
Meet the coordinator: Iain Ellis
Iain has worked on the biology and ecology of native fish for over fifteen years with particular focus on the conservation of threatened species, and adaptive management to preserve and recover native fish habitat.
The Native Fish Recovery Strategy
The Native Fish Recovery Strategy will supplement and build on existing knowledge, generated under the previous native fish strategy and will be implemented collaboratively with Basin state governments, First Nations and the wider community. It’s development will be delivered concurrently with the implementation of high-priority implementation activities including the Lower Darling Fish Monitoring and Engagement program and the Native fish emergency response plan.