Bycatch describes animals caught unintentionally by fishing gear, including non-target species and undersized fish.
Many fishermen seek to catch a "target" species. When fishermen catch something that they didn't intend to, such as a different fish species, a cetacean, sea turtle or seabird, that is called bycatch.
Bycatch is a huge problem in some fisheries. Prior to the 1990s and improvements in the yellowfin tuna fishery, hundreds of thousands of dolphins were caught in purse seine nets each year. Bycatch is not only a problem for environmentalists and resource managers. It is a problem for fishermen, because bycatch can damage fishing gear and cause losses in fishing time. In many cases, bycatch needs to be thrown back, and in some cases, the animals are already dead when they are returned to the ocean.
A 2005 study by the Food and Agricultural Organization of the United Nations estimated global bycatch at 8% of the total catch.
Solutions to Bycatch
Over the years, scientists and fishermen have been working on the bycatch problem. This work has resulted in a great reduction in bycatch in some fisheries, such as the reduction of sea turtle bycatch after fishermen were required to install turtle excluder devices (TEDs) in their nets, although bycatch is still a problem, particularly in areas were there is a lack of funding or enforcement to deal with the bycatch problem.