Preliminary results from the first large-scale test of specially designed fishing hooks indicate they can reduce the number of endangered sea turtles killed in long-line fishing operations by as much as 90 per cent, while having almost no effect on the catch rate of targeted fish, according to the World Wildlife Found (WWF).

WWF said in a statement that the study - for which WWF and others provided financial and logistical support - took place over the past year in Ecuador's tuna and mahi-mahi fisheries and involved 115 Ecuadorian fishing vessels.

The reduction in bycatch occurred when the boats replaced their traditional 'J' shaped hooks with specially designed circle hooks, which are less likely to get swallowed by turtles says the statement.

"Also encouraging was the fact that catch rates for tuna were almost identical regardless of whether circle or 'J' hooks were used," it adds.

"This is a win-win situation," said Moises Mug, Fisheries Coordinator for WWF's Latin America and Caribbean programme.

"We were looking for a way to save the turtles without putting the fishermen out of business.

The preliminary results indicate we've found it."

WWF claims that incidental death as a result of traditional, long-line fishing operations is one of the main reasons for the precipitous decline of loggerhead turtles and of giant leatherback turtles. The WWF statement said their numbers in the eastern Pacific have plunged by more than 90 per cent over the past 20 years.

In 2004, WWF launched a global competition called Smart Gear to find the most practical, innovative designs for fishing gear that reduce wildlife deaths.