WASHINGTON -- Commercial fisheries in the United States kill a pound of fish for every four pounds intentionally caught, jeopardizing efforts to restore some struggling stocks, scientists said yesterday.
A tally of the nation's yearly ''bycatch" -- unwanted fish that are caught and, in most cases, die before being thrown overboard -- was conducted by scientists Jennie Harrington, Andrew Rosenberg, and Ransom Myers.
Their peer-reviewed study, sponsored by the environmental group Oceana and published in the December issue of Fish and Fisheries magazine, found that 1.1 million tons of fish annually are thrown away with every 4 million tons caught in commercial nets.
''We can and should do better," said Rosenberg, dean of the University of New Hampshire's College of Life Sciences and Agriculture and a member of a federal commission that studied ocean policy. ''This sort of waste undermines efforts to recover those depleted resources."
Most of the fish -- such as skate, monkfish, swordfish, tuna, sharks, salmon, and halibut -- are snared by shrimpers' nets in the Gulf of Mexico or in the huge trawling nets some vessels use to reach the ocean floor.
The Gulf's shrimpers, for example, catch 114,000 tons of shrimp a year but discard four times that weight in snappers, mackerel, Atlantic croaker, crabs, and porgies.
In response to the study, National Oceanic and Atmospheric Administration Fisheries, part of the Commerce Department, said yesterday that federal efforts to use newer fishing gear and ways of managing have cut bycatch by 50 percent in the Gulf shrimp fishery and by substantial margins in virtually all other US fisheries. The federal agency, responsible for managing US marine resources from 3 miles to 200 miles offshore, keeps regional bycatch statistics, but does not compile them nationally.
Zeke Grader, executive director of the Pacific Coast Federation of Fisherman's Associations based in San Francisco, acknowledged the bycatch problem. He said the government should charge a seafood fee to establish a multibillion-dollar trust fund -- an idea proposed by the federal commission and some in Congress -- to pay for more selective fishing gear and better fisheries research.
''It's both a concern for other fisherman and for the health of the stocks," he said. ''There's no real easy answer."