Brazilian fisherman Antonio Zeferino Santos Costa works with others to pull in their net at low tide on sand flats at the mouth of the Amazon River in Curuca, May 20, 2009. Santos Costa and his fellow fishermen capture about 200 kgs (440 lbs) a day of species ranging from mullet, bass, piraiba and piramatuba catfish, sardines and yellow weakfish, among others, in the mixture of fresh and saltwater that characterizes the mouth of the world's largest river. Picture taken May 20, 2009. REUTERS/Paulo Santos (BRAZIL ENVIRONMENT SOCIETY)