One of the toughest fish in the Murray – the Murray hardyhead – is at risk of becoming a permanent casualty of the unprecedented low water allocations announced today.
“Years of dry conditions are putting huge pressure on irrigation farmers and their families, and the river is also being hit really hard. Murray hardyhead are one of the toughest fish in the river and have survived droughts over thousands of years, but they’re going to be king hit by this big dry,” said Dr Paul Sinclair Environment Victoria’s healthy rivers campaign director.
There are only seven known populations of Murray hardyhead left in the world. Three are in South Australia and four in northern Victoria. The fish is so tough it’s been living in wetlands with a salinity levels of 20 000 EC. Water can drunk safely by people at 800 EC.
In the past the Murray River has had an environmental entitlement allocated to help keep the last populations of endangered species like hardyhead on life-support. This year the environment’s allocation will be 5% of its total entitlement, just the same as irrigation water entitlements.
“It is vital that the good work catchment management authorities are doing to protect the last refuges for fish and wildlife is accelerated. If we don’t keep some really important refuges alive, we’ll lose more of our unique species forever,” said Dr Sinclair.
“Murray hardyhead came out of nature’s factory thousands of years ago. They’re not making any more of them.”
Ten of the 22 native fish species that are known or suspected to have previously existed in the Lower Murray-Darling catchment are either locally extinct or in danger of becoming extinct.
Native fish have survived droughts in the past by finding refuges. But years of unsustainable water use have destroyed many of these refuges. Approximately 90% of wetlands in the Murray-Darling Basin have been lost. For native fish dry years are now drier than naturally occurred because of the impacts of water extraction. In an average year 60% of the Goulburn River’s flow is taken can be extracted for irrigation, in a dry this can be 80%.
International research has found fish populations in rivers already suffering from huge extractions of water are at increased risk from reduced inflows caused by climate change. Up to 22% of the worlds fish species are in danger of extinction.