Australia Launches Study of Sharks, Rays, Sawfish

SYDNEY, Australia, February 17, 2003 (ENS) - Federal and state marine research agencies and the fishing industry have joined in a three year study aimed at ensuring the sustainability of shark, ray and sawfish species in the waters off northern Australia.

The study will assess the effects of commercial fishing on shark, ray and sawfish species which are often taken as bycatch. They will also investigate the status of sharks targeted by northern fisheries, to identify those most in need of protection. Results of the study will underpin a national approach to the risk assessment of Australian sharks, rays and sawfishes, and contribute to regional, national and international plans for their conservation and management.

Looking west to the Indian Ocean from Australia's north coast (Photo courtesy NOAA)

In each state, trained observers will accompany fishing boats to identify and record the catch, and to collect biological information and samples for genetic analysis. Commercial fishers would be trained to record these details on an ongoing basis.

"Sharks, rays and sawfish are vulnerable to fishing as they grow slowly and produce fewer young than most bony fishes," said John Salini of CSIRO Marine Research.

Shark in Australian waters (Photo courtesy NOAA)

But the species composition of such catches is poorly documented, offering few clues to the impact of fishing on the 128 different types of sharks, rays and sawfishes that inhabit the region.

"These catch and biological records will be combined with ecological knowledge to enable accurate stock assessments of the major target species, such as the blacktip shark and the spot-tail shark," Salini said. "We will also use the information to identify potentially higher risk or vulnerable species that may require coordinated management initiatives."

Tropical sawfish species are at risk worldwide, with little known about their accidental capture. Two northern Australian species, the dwarf sawfish and the green sawfish, both caught in gillnets, are listed as endangered.

The Sawfish. Pristis pectinatus, Latham (Drawing courtesy NOAA)

The United Nations has developed an International Plan of Action for the Conservation and Management of Sharks amid concern about overfishing that has put most shark species at risk.

In Australia, a National Plan of Action for the Conservation and Management of Sharks is coordinated by the Department of Agriculture, Fisheries and Forestry. The 1999 Environment Protection and Biodiversity Conservation Act requires export fisheries to be assessed for their ecological impacts.