one environmentalist worried about the dolphins is marine biologist stefan austermuhle. >> the pacific ocean in fronont of the peruvian coast is the most bibioproductive ocen in the world. we are catching here 10% of the world's fish catch. that meansns there's a lot of fd around in form of anchovovies and other small pelagic fish. and where there's a lot of food, all the guyuys that eat that fod will come by and have their part. and that means we h have here more than wh--uh, 30 species of whales and dolphins. the fact that dolphins are killed in shark fisheries here in peru is an open secret in the entire industry. everybody that works in the fishing industry knows it. all the government representatives know it. and even the ngogos working in the ocean, they know it. but nobody talks about it, because you can't prove it. how do you want to prove something that appears-- that happens tens or hundreds of miles offshore that you have never even seen? >> we were introduced to a former fisherman who agreed to speak openly about the hunting of dolphins. >> [speaking spanish] >> i went to s