Native fish dying out in lakes
WA's freshwater fish are dying. An unprecedented investigation of the State's lakes reveals nearly 60 per cent contain no native species.
The year-long survey by the Department of Fisheries and National Resource Management covered from Geraldton to Busselton and east to Northam, looking at the fish bio- diversity of 114 lakes. Only 50 lakes contained any native fish.
Department scientist Craig Lawrence said the findings were alarming, particularly because of the large number of feral fish which have been partly blamed for the rapid native decline.
Loss of habitat because of urban sprawl and the drying up of nearly half the lakes were also blamed. "For the first time we are getting a clear picture of the situation and the results are concerning," Dr Lawrence said.
With native fish a major source of food for recreational fishing species and keeping down insect populations such as mosquitoes, the department will look at breeding native fish for restocking.
"These are the species that control Ross River virus and, in the future, dengue fever, and they are also the basis of the food chain," Dr Lawrence said. "It would be very hard to have a recreational marron industry if there was no food for the marron."
Only 9 per cent of the lakes contained exclusively native fish species, 66 per cent had introduced freshwater species and 12 per cent had no fish.
Last Updated on Sunday, 10 June 2012 17:45