Shrimp Boats Kill 44,000 Turtles, Scientists Say : Environment: A panel finds the annual drowning of threatened sea animals to be four times official estimates. The toll could be cut 97% with escape doors.

Shrimp boats working the United States’ southern Atlantic coast and the Gulf of Mexico may have been killing as many as 44,000 threatened and endangered sea turtles each year--four times the official government estimate--a panel of the National Academy of Sciences reported Thursday.

The drownings, the panel concluded, theoretically could be reduced 97% by the full use of nets equipped with escape doors. That could make the shrimping industry compatible with protection of the huge turtles, whose numbers have dropped alarmingly.

On the Mexican coast of the Gulf of Mexico, where 40,000 Kemp’s ridley turtles were observed nesting on a single day in 1947, the population of nesting females now may be no more than 350, the panel said. Although populations of green and loggerhead turtles have stabilized in some areas of Florida, the number of loggerheads continues to decline on the beaches of Georgia and South Carolina.

The academy study grew out of a furious debate over requiring shrimp nets to be equipped with turtle exclusion devices, or TEDs. Shrimpers, particularly in the Gulf of Mexico, bitterly argued that the trap door nets that allow the turtles to escape would cause them to lose 40% of their catch.

Ironically, supporters of the shrimpers requested the study, hoping that it would debunk the National Marine Fishery Service’s estimate that 11,000 turtles are killed each year by the shrimpers.

Environmentalists hailed the report’s outcome Thursday.

“Opponents of the federal regulations have argued that sea turtles are not really endangered, that shrimpers do not kill many sea turtles, and that TEDs are not needed for sea turtle conservation,” said Michael Bean, an attorney for the Environmental Defense Fund. “But the academy’s study forcefully rejects all of these contentions.

“The Commerce departments of the last two administrations, at least three federal courts, and now the National Academy of Sciences have sided with the turtles,” he continued. “Now it is time for shrimpers in the northern Gulf to do what most shrimpers elsewhere have already done . . . : face up to the need to act responsibly to end the slaughter of sea turtles.”

Regulations requiring the use of turtle-safe nets were first issued in 1987, and a fishermen’s organization called Concerned Shrimpers of America went to court in an unsuccessful effort to block implementation.

Last summer, Commerce Secretary Robert A. Mosbacher set aside the net regulation and proposed to protect turtles by requiring trawlers to pull up their nets every 105 minutes to allow entrapped turtles to escape before they drown. He was taken to court by the National Wildlife Federation, and a federal judge in Houston--calling his action a “total abrogation of the regulations”--ordered the safe net requirement enforced.

With the regulation now in place, shrimp boat operators can be fined as much as $8,000 a day for operating without the safety nets, but no figures were available Thursday on arrests or fines.

Academy panel member Charles H. Peterson of the University of North Carolina said the findings in the new study will support federal efforts to protect the endangered turtles. But they also indicate that nets equipped with the excluder devices are not effective under all circumstances.

In rivers and coastal waters where heavy grass makes the safe nets ineffective, turtles can be protected by limiting the tow times to 40 minutes during the summer and 60 minutes during winter.

In other areas, the report suggests that the requirements for turtle safe nets be expanded. At present, regulations do not require the use of TED-equipped nets along the Georgia and Carolina coasts beyond the end of August. But the panel said that turtles, including the severely endangered Kemp’s ridley, remain in that area at that time of the year and are being killed.

Although the panel said that shrimp nets are the chief threat to survival of endangered turtles, hundreds more are being killed by other fishing operations--collisions with boats, dredging operations and the destruction of abandoned oil rigs.

No estimate was made, but the panel said the 24,000 tons of plastic packaging dumped into the ocean each year pose an additional threat, especially to species that feed on jellyfish and confuse floating plastic for their favorite food. But for efforts of the Mexican government, Peterson said, the Kemp’s ridley turtle might already face extinction. For the last 10 years, the Mexicans have carefully protected the nesting females and their hatchlings at Rancho Nuevo, the species’ primary nesting beach.

The area where their eggs are laid was seriously damaged when Hurricane Gilbert hit Mexico’s Gulf Coast in the fall of 1988, leaving gravel and rubble where there had been sand, and further threatening their survival.