Irrigation is essential for farmers and communities in north west NS W. T he two major types of water extraction methods used in the region are canal systems and direct pumping.

Canal systems with regulatory weirs and diversion channels, can potentially affect native fish in ways similar to those outlined in the ‘River C onnectivity’ section. M igrating fish are restricted from accessing preferred habitat and food, whilst native fish larvae and juveniles could be diverted from the main river channel.

Pump systems, which extract water from rivers into on-farm storages, may also affect native fish populations. T he pumps themselves could extract or divert fish away from appropriate habitat. Fish of all size classes may also be susceptible to injuries or death during this process.

Research is currently underway to reduce the potential impact of irrigation systems on native fish in the M urray-Darling Basin. It is anticipated that the results from these studies will improve irrigation management practices by developing engineering solutions and operational improvements that reduce the effect on native fish.

Management strategies being considered are already implemented with some degree of success in other countries (e.g. USA ). T hese strategies include aligning extraction times with non-critical times for native fish and larvae migration by altering the operations of irrigation diversions, using behavioural exclusion devices, or installing fish screens to reduce extraction and divert fish back to the river.

MANAGEMENT OPTIONS

Improve and implement fish friendly irrigation practice

MANAGEMENT ACTIONS

• Stay informed of new research into irrigation systems and native fish, adopting management recommendations as appropriate and seeking funding opportunities from local NRM groups, such as your CMA
• Align extraction times with non-critical times for native fish and larvae migration (see migration table below for more information)