AUSTRALIA – In a world first, researchers at The University of Western Australia and Western Australia’s Department of Fisheries have bred one of Australia’s rarest fish – the critically endangered Western Trout Minnow.
Dr Craig Lawrence, a principal research scientist from the Department of Fisheries and an Adjunct Associate Professor from UWA’s School of Animal Biology, said it was a major breakthrough in efforts to prevent the extinction of this rare species.
Winthrop Professor Peter Davies, Pro Vice-Chancellor, said the success of the project was a wonderful milestone to mark the 20th anniversary of a very productive partnership between UWA and the Department of Fisheries in aquaculture and native fish breeding research.
“UWA is committed to achieving research excellence in our world-class facilities such as the UWA Aquaculture and native fish breeding laboratory,” Professor Davies said.
The Western Trout Minnow was the first freshwater fish species in Australia to be listed as critically endangered and is the only fish species listed as critically endangered in WA, where they remain in only a few kilometres of river on the south coast.
In 2006 it was estimated that between 2,000 and 5,000 remained in the wild.
Dr Lawrence and his team developed a hypothesis that the fish spawned in response to specific environmental parameters and if their timing and collecting techniques were exactly right, it may be possible to either collect mature stock from the wild and spawn them in UWA’s aquaculture and native fish breeding laboratory, or to trick the fish into spawning in the wild in a system where the eggs could be collected.
“The team achieved both hatchery spawning of adults, as well as transport, incubation and hatching of wild spawned embryos,” Dr Lawrence said.
“Working round the clock in the UWA hatchery, the researchers were able to hatch and rear their precious larvae to produce around 2,000 fry.
“In addition to ensuring that environmental conditions were ideal, hatchery rearing protected the eggs and larvae from predators and ensured a constant supply of food for the young fish larvae, resulting in much higher survival rates than could ever be expected in the wild.”
These precious fish will now be used to develop a captive breeding program to save the species from extinction, by establishing an “Ark” or repository population at the UWA laboratory and, in the longer term, restocking water bodies.
The research is part of a broader study on the ecology and distribution of threatened freshwater fish of south-western Australia, funded by the WA Government’s State Natural Resource Management Program and undertaken by Department of Fisheries, The University of Western Australia and Murdoch University.