Unwanted Fish: Bycatch
By Josie Lucier
Bycatch contributes to the problem of lower marine populations. Large amounts of unwanted fish and other marine animals are caught along with the sought-out fish. Bycatch happens because today’s fishing gear is very efficient, typically covers a large area, and the gear is not species-specific so others get caught. 8-25% of total global catch is tossed overboard either dead or soon to be dead. That means that about 27 million tons of fish are thrown out each year. And the accidental catches don’t just include fish. Whales, dolphins, porpoises, and endangered sea turtles also die while tangled in nets.
Bycatch in Shrimp fisheries
Some of the biggest offenders are shrimp fisheries. They use a method of fishing called trawling. Trawls are fishing nets that are pulled along the bottom of the sea or in midwater. Shrimp trawls have specially designed nets which makes escaping extremely difficult, especially for the bycatch. Shrimp trawl fisheries catch 2% of the world total catch of all fish by weight, but produce more than one-third of the world total bycatch. In some of the worst cases, for every pound of shrimp caught, up to six pounds of other species are thrown out. Recent sampling from the South Atlantic rock shrimp fishery over a two-year period found that rock shrimp amounted to only 10% of total catch weight. Iridescent swimming crab, dusky flounder, inshore lizardfish, spot, brown shrimp, longspine swimming crabs, and other bycatch made up the rest.