STUDENT BAGS HONOURS WITH ENDANGERED NATIVE FISH

Published 5 February 2001

Extensive research in waterways near Evans Head in northern NSW has revealed unprecedented numbers of the rare Oxleyan Pygmy Perch, a tiny native fish that shares the international 'red list' of endangered species* with animals such as the Giant Panda and the Cheetah.

According to findings just released by Jamie Knight, an Applied Science honours student at Southern Cross University, the threatened freshwater species has been found to exist in 25 waterbodies in and around the Broadwater National Park. Prior to his research the Pygmy Perch had only been recorded in four NSW localities in the past twenty years.

The range of the fish is restricted to the coastal heathlands of Southeast Queensland and Northeast NSW. It is recognised as one of Australia's most endangered species and NSW Fisheries is expected to use Mr. Knight's findings to help draft a recovery plan to ensure the fish's long-term survival. The Evans Head area is one of the most important known habitats for the species' long-term conservation.

Mr. Knight, who received funding from Southern Cross University, NSW Fisheries and Australian Geographic, said he had investigated 82 creeks and lakes in a two-month period in late 2000. He had netted and released a total of 566 fish from 25 of them.

"As I discovered, their preferred habitat is shallow water stained dark with Tea-tree acids, away from flowing water, near steep/undercut banks, and amongst dense aquatic vegetation, leaf litter beds and snags," he said. "Such locations and their tiny size make them virtually impossible to detect from the surface with the naked eye."

The fish, which grow no larger than 5cm, were previously known to exist in a total of only thirty locations in NSW and Queensland, which makes Jamie Knight's findings highly significant.

He said their major threat appeared to be land clearing, sand mining, recreational activities, water pollution and the widespread presence of the equally tiny, highly predatory Gambusia or 'Mosquito fish', recently renamed the 'Plague Minnow' by NSW National Parks & Wildlife Service. This fish has also been the subject of extensive study by Mr. Knight.

"With a history resembling the cane toad's, it was introduced to Australia from southeastern USA in 1926 on the premise that it would help control mosquitoes," he explained. "Not only did it fail to do that but it has had an adverse interaction with at least twenty of Australia's threatened native fish species as well as several frog species. It is very common in Australian fresh water habitats and in fact is now the world's most widely distributed fish."

* Endangered species are those which have suffered a population decline over all or most of their range, whether the causes are known or not, and which are in danger of extinction in the near future. There are 12 species of Endangered Australian fish. A total of 89 species - approximately one third of Australia's fish - are either threatened with extinction, considered to have significantly declined in distribution or are found in restricted areas.

For further information please contact Mr. Jamie Knight on (02) 6628 6900 or Mr Robin Osborne, Media Liaison, Office of the Vice-Chancellor, (02) 6620 3039 Mobile: 0418 431 484 Email: rosborne@scu.edu.au