The Reintroduction of the Murray Crayfish in South Australia

Image: Nick Whiterod

Two University of Adelaide Ecologists first introduced this idea of returning the Murray crayfish to South Australia in the 1990s, late Keith Walker and Mike Geddes. Now, more than 30 years later, this vision is coming to life. 

Nature Glenelg Trust, a non-for-profit organisation, has worked in partnership with First Nations community, a natural resource management agency, fisheries agencies from three states and a private aquaculture facility to make it happen. Reintroductions are essential to help aid the recover the threatened species. 

Murray crayfish were once widespread in the southern Murray-Darling Basin. First Nations people were able to sustainably harvest the crayfish for thousands of years, but with settlement from the Europeans, commercial and recreational harvest have impacted the species to the point that they disappeared from South Australia in the last 40 years. By 1955, 15 tonnes of Murray crayfish were being taken from New South Wales rivers annually. Murray crayfish became a protected species in South Australia during the 1980s due to the over-harvesting conducted.  Overharvesting wasn’t the only challenge. Murray crayfish rely on free-flowing, oxygen-rich water, but river regulation, poor water quality, and blackwater events worsened their decline. 

The crayfish were released back into SA waters during winter 2023, and a further 200 during winter 2024. Each crayfish has a tracker tagged to regularly detect their movements and activities. As a keystone species, Murray crayfish play fundamental role in the ecosystem. Having them return to the river may prove to have greater ecological benefits.

Going forward, the program will require further commitment to be successful and extra crayfish are to be added as the years go on. The existing reintroduced population will be monitored to ensure the population and their range continue to grow, remaining protected from fishing and local authorities. 

To read more about this amazing initiative, click here!

This initiative is a partnership between Nature Glenelg Trust and the Murraylands and Riverland Landscape Board through funding from the landscape levies, with support from NSW Fisheries, Victorian Fisheries Authority, not-for-profit organisation OzFish Unlimited, North West Aquaculture, the River Murray & Mallee Aboriginal Corporation (RMMAC), CSIRO and the Department of Primary Industries and Regions SA (PIRSA).