A shocking new report from the conservation organization Oceana reveals staggering levels of waste caused by U.S. fisheries. According to the report, up to 2 billion tons of fish and other species die needlessly every year. This adds up to 500 million seafood meals every year, while also killing astonishing numbers of dolphins, sea turtles, whales, sharks and other endangered species.

The report covers bycatch — the capture of "non-target fish and ocean wildlife" either by accidentally catching unwanted species or by catching too many fish.

"Anything can be bycatch," Dominique Cano-Stocco, campaign director at Oceana, said in a news release. "Whether it's the thousands of sea turtles that are caught to bring you shrimp or the millions of pounds of cod and halibut that are thrown overboard after fishermen have reached their quota, bycatch is a waste of our ocean's resources. Bycatch also represents a real economic loss when one fisherman trashes another fisherman's catch."

The most bycatch, Oceana found, came from three types of fishing operations: those that employ open ocean trawl, longline nets or gillnets. "Hundreds of thousands of dolphins, whales, sharks, sea birds, sea turtles and fish needlessly die each year as a result of indiscriminate fishing gear," explained Amanda Keledjian, a marine scientist at Oceana and the author of the report (pdf). "It's no wonder that bycatch is such a significant problem, with trawls as wide as football fields, longlines extending up to 50 miles with thousands of baited hooks and gillnets up to two miles long."

Using data from the National Marine Fisheries Service, Oceana identified nine "dirty fisheries" in the U.S., which they say account for more than 50 percent of all reported bycatch. The Southeast Snapper-Grouper Longline Fishery, the worst fishery on the list, has a 66 percent discard rate and captured more than 400,000 sharks in one year. The Southeast Shrimp Trawl Fishery, according to the report, kills thousands of sea turtles every year and one pound of billfish for every pound of shrimp that it lands. The California Drift Gillnet Fishery, which has a 63 percent discard rate, entangled almost 550 marine mammals in its nets over a five-year period.

Oceana says there are solutions to all of this waste, including banning drift gillnets, requiring turtle excluder devices in trawling nets, and moving some fishing operations away from "bycatch hotspots." The organization is also calling for greater government oversight of the fishing industry, in part to ensure that people are following the rules and regulations. "There's evidence that fishermen don't do [things like using turtle excluder devices] if they're not being watched," Cano-Stocco told the Huffington Post.

Reducing fishing bycatch would be a "win/win" for both fishermen and conservationists, Oceana said, as it would allow more species to thrive while making sure that commercial fish that are caught are not wasted.

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