Latest fishing closure protested

The National Marine Fisheries Service said it was required to take the action because the number of porpoises dying as a result of being ensnared in gillnets - fixed lines placed on the ocean floor - exceeds rates set under a 2010 management plan.

But the ruling is raising alarm among commercial gillnet fishermen, who said it will only add to the economic stress they are facing because of other regulatory moves in recent years.

Most of those gillnetters belong to Sector 3, a cooperative in Gloucester with 34 members, according to Jackie Odell, executive director of the Northeast Seafood Coalition, which represents commercial groundfishermen from Maine to Long Island.

“They are furious,’’ Odell said of the gillnetters. “We are trying to get more flexibility for fishermen to be able to fish in times and in areas where groundfish stocks are located and abundant and where there are healthy stocks like pollock. . . . This goes completely contrary to all we are working on.’’

Odell warned that the closure could have a “tremendous impact on the day boat fishermen who are already tremendously impacted’’ by other rules.

Harbor porpoises, a protected species under the federal Marine Mammal Act, inhabit ocean waters extending from Nova Scotia to North Carolina, according to David Gouveia, coordinator of the marine mammal and sea turtle conservation program for the National Marine Fisheries Services northeast regional office in Gloucester.

Under the Marine Mammal Act, the Fisheries Service must develop management plans to protect porpoises or other mammals whenever data show that they perish as bycatch in the harvesting of other fish at a rate that threatens their survival as a healthy population.

The Fisheries Service in 1998 implemented steps to protect porpoises in northeast waters after bycatch rates had soared to as high as 1,600 porpoises a year, well above the 480 considered a safe level for the species, according to Gouveia. The measures, developed with the help of a team that included industry members, included closing specific areas to gillnetters during certain times of the year and requiring gillnetters to place “pingers’’ - acoustic devices that deter porpoises - on their nets.

Gillnets are targeted under the rules because they are responsible for about 90 percent of the porpoise deaths resulting from fishing bycatches, Gouveia said. Porpoises that become entrapped in fixed nets die as a result of drowning.

The 1998 plan initially worked, Gouveia said, noting that annual bycatch rates for the porpoises fell as low as 320 animals.

But he said starting in 2005, “We noticed it started to go in the wrong direction,’’ with bycatch rates climbing again.

In response, the agency worked with a new team to develop an amendment to its 1998 plan.

That amendment, adopted in 2010, reflected a conclusion that the rise in porpoise deaths was attributable to bycatches occurring outside the existing management areas and to fishermen not complying with the pinger rules. The new measures included expanding the number and size of management areas and allowing for additional targeted closures in designated areas should bycatch rates exceed specified thresholds.

The designated areas, selected using data showing relatively high numbers of porpoise deaths in preceding years, included areas labeled the Coastal Gulf of Maine, Cape Cod South Expansion, and Eastern Cape Cod.

The recently announced closure affects the Coastal Gulf of Maine, an area that encompasses waters off southern Maine, the coast of New Hampshire, and the North Shore, including Gloucester.

The Fisheries Service established a threshold bycatch rate for porpoises that would be calculated as the average of two seasons. But the number of bycatches recorded in the first season in the Coastal Gulf of Maine area was so high that the agency concluded that even with no porpoise deaths the second year, the threshold would be exceeded. That triggered the need to close the area for two months in the fall.

Gouveia said a key factor in the high bycatch rate was the relatively low rate of compliance with the pinger rules, noting that just 41 percent of gillnetters were adhering to the requirements.

“Nobody wanted to use this fall-back mechanism,’’ he said of the closure. “It was an extraordinary provision to use only if things went awry.

“Unfortunately things went awry based on the data. . . . That unfortunately triggered that action.’’

Odell said gillnet fishermen want to know what calculations the Fisheries Service is using to determine the “takes are so high.’’

In addition, she said they want to be “actively engaged in the process. They don’t want to be told we found out we are having compliance issues and we are shutting you down.’’

John Laidler can be reached at laidler@globe.com.