American fishing operations discard more than a fifth of what they catch each year, according to a new report by a team of U.S. and Canadian scientists.
The study, which was commissioned by the marine advocacy group Oceana and appears in the December issue of the journal Fish and Fisheries, represents the first comprehensive accounting of the amount of "bycatch" in the United States. Fisheries consultant Jennie M. Harrington, Dalhousie University professor Ransom A. Myers and University of New Hampshire professor Andrew A. Rosenberg used federal data collected from 1991 to 2002 to calculate which regional fisheries inadvertently kill the most unwanted fish.
The Gulf of Mexico topped the list, largely because its shrimp fishery had 1 billion pounds of bycatch -- half the nation's wasted fish in 2002. Gulf shrimpers, which typically drag trawl nets with steel doors across the ocean floor, discard about four times as many fish as they keep, according to the study.
U.S. fisheries on average throw away 22 percent, or 1.1 million tons, of the fish they catch.
"The scale of the problem here is enormous," Myers said, adding that the annual wasted fish would fill every bathtub in a city of 1.5 million people. "And it's an insidious problem, because we cannot have the recovery of fish stocks as long as they keep getting caught as bycatch."
A variety of unwanted marine species become trapped in fishing gear by vessels seeking a different catch and are then thrown away, including noncommercial species such as jellyfish and small crustaceans. The researchers did not include protected species, such as turtles, as well as mammals and birds in their study.
Southern Shrimp Alliance President Joey Rodriguez, a third-generation shrimper in Alabama who represents fishermen from North Carolina to Texas, said that shrimpers have adopted more environmentally sensitive gear in recent years but that they continue to go after shrimp "the only way we know how to catch 'em. You're going to catch a lot of things not trying."
Rodriguez, who said the Gulf of Mexico's shrimping fleet is wasting fewer fish because overseas competition and recent hurricane damage has cut its size to half of what it was four years ago, said his members are open to adopting new techniques as long as they are affordable. "We just want to catch shrimp," he said.
Bob Mahood, executive director of the South Atlantic Fishery Management Council, said his region had helped reduce bycatch over the past decade by demanding that fishing operations adopt different gear. In the snapper and grouper fishery, the council has barred entanglement nets, trawling and mesh traps that lure fish with bait.
Most of the region's bycatch consists of commercially "nonessential species," Mahood said, though he added, "If you look from an ecosystem point of view, they obviously have some ecosystem value."
Mahood said that his regional council had called on shrimpers in 1996 to use gear aimed at reducing bycatch by 40 percent but that he did not know if the strategy had worked. "There hasn't been a whole lot of follow-up," he said.
Susan Buchanan, a spokeswoman for the National Oceanic and Atmospheric Administration, said the agency "remains committed to further reducing bycatch through innovative technologies and management approaches, and NOAA's investment in bycatch reduction programs have cut commercial fishing bycatch considerably in the last decade. NOAA Fisheries data shows that bycatch has dropped 50 percent in the Gulf shrimp fishery and substantially in virtually all other U.S. fisheries, benefiting the ecosystem and protecting our valuable marine resources."
Although federal authorities track bycatch by placing observers on some vessels, their statistics are not comprehensive.