"Every type of fishing gear has bycatch," said Martin Hall of the Inter-American Tropical Tuna Commission at the AAAS Annual Meeting in San Francisco. "All gear can be improved."

For example, Hall says that if a boat using a purse seine net to catch tuna reverses direction, it changes the shape of the net, separating any dolphins caught in the net from the tuna and allowing the dolphins to escape. Using this process has been shown to cut bycatch to 1% of its original level.

With technological rather than operational solutions in mind, WWF recently launched its third annual Smart Gear Competition for fishing gear designs that reduce marine bycatch. The first prize is $30,000 while two runners up will each receive $10,000. The winning designs will be those judged most practical and cost-effective for reducing bycatch of any species. Entry is open to all, including fishermen, professional gear manufacturers, students, engineers, scientists and "garden shed" inventors, as long as they get their entries in by 31st July.

"We want to encourage people from different countries and backgrounds to enter this competition to make fishing practices smarter," said James Leape, director general of WWF. "Often the best innovations come from fishers themselves. This is a unique opportunity to hear about practical solutions to help tackle one of the greatest threats to our seas."

The 2006 Smart Gear competition's winning design placed strong magnets next to baited hooks to prevent sharks, which can detect magnetic fields, from dying on fishing lines. The system will undergo trials in the spring and summer before potentially being brought into commercial use.

Other technological approaches to improving fishing gear include adding acoustic devices known as pingers to nets to scare bycatch species away, attaching streamer lines to the portions of fishing lines that are above the water to prevent seabirds approaching, and using circle-shaped rather than more traditional hooks on longlines to reduce turtle catch.

Kiki Jenkins of Duke University, also speaking at the AAAS meeting, added that fishers have invented some of the most widely adopted and successful gear improvements. "Technology is more likely to be adopted if promoted by a peer," she said.