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This is Scientific American's 60-Second Science. I'm Cynthia Graber. This will just take a minute.

The numbers of fish and other ocean life have dropped dramatically in the past few decades. That's because of commercial overfishing, and something called bycatch.

More than 300 thousand small whales, dolphins and porpoises¹ die due to commercial fishing each year.

And more than 250 thousand endangered sea turtles are killed on longlines set for tuna, swordfish, and other fish.

So here's a charge for any inventors out there: Create new fishing gear² to reduce bycatch. Top prize? Thirty thousand dollars.

It's the fifth International Smart Gear Competition sponsored by the World Wildlife Fund.

"The Eliminator," a fishing net, was a winner in 2007, designed to reduce bycatch of cod³ in the haddock fishery.

The Eliminator takes advantage of how fish swim. It has large openings at the bottom of the net. Because when haddock face a net, they swim up to escape and get caught. But other groundfish, like cod, swim down to try to break out. So the cod can escape through openings at the bottom.

The Eliminator is now being used in New England and in Europe.

The current competition is open from March 1 through August 31. So get your net ready, and cast your ideas.

Thanks for the minute. For Scientific American's 60-Second Science, I'm Cynthia Graber.