Native fish communities in the Murray-Darling Basin are highly degraded due to declines in habitat and water quality, barriers to migration, invasive pests and diseases.
Recent initiatives seeking to control Carp through biocontrol, and recover/deliver water through implementation of the Basin Plan will contribute to recovery of basin waterways and fish communities. However there is also a need to rehabilitate native fish habitat, address coldwater pollution, re-establish populations of locally extinct native species, prevent loss of native fish eggs and larvae to pumps and diversions, and restore fish migratory routes. Integrated measures such as these will help to deliver enduring outcomes from environmental watering and pest fish control, and ensure that native fish thrive as carp numbers decline.
Complementary Measures (CM's) seek to deliver basin-wide recovery of native fish populations under broad themes, including:
• Implementation of Australia’s carp biocontrol program
• Installation of screens on pumps and diversions
• Re-establishing native populations through re-stocking
• Putting the habitat back
• Enhancing fish passage
Addressing Cold Water Pollution
Significant investment in CM's is being considered as a means of meeting Basin Plan outcomes without unduly impacting rural and regional communities. Discussions are underway to pursue the remaining investment under the Sustainable Diversion Limit Offset Program (through MDBA). The funding will only become available if a quantum of environmental flows can be defined, to represent the volume of water that would not need to be recovered from irrigators should these additional actions be undertaken. It is imperative that the activities are demonstrated to deliver equivalent ecological outcomes with a defined water saving. Otherwise, the initiative will not meet funding guidelines.
The challenge is therefore to assess the expected benefit of various measures seeking to facilitate recovery of native fish, and compare these against the equivalent amount of flow required to achieve the same outcomes. This process needs to be finalised by early 2017 in order to meet critical funding deadlines under the basin plan rollout.
Final report
complement water recovery effort to date and further drive ecological outcomes independent of water recovery aspirations. The challenge is therefore to assess the expected benefit of various measures seeking to facilitate recovery of native fish, and compare these against the equivalent amount of flow required to achieve the same outcomes.