Lobsters heading for the deep

While their plight might not be as dramatic as that of polar bears drowning in the melting Arctic seas, the lobsters of Long Island Sound could be this region's poster child for climate change.

Lobster populations across all of southern New England, from the elbow of Cape Cod to the Sound, have sunk to what fisheries biologists consider dangerously low levels. Meanwhile, their kin to the north flourish, accompanied by a healthy fishery for this favorite culinary crustacean.

Since a major die-off in the Sound in the late 1990s, researchers have been studying possible causes, with most pointing to some convergence of factors including shell disease, overabundance of predators, toxins and pesticide residues from efforts to eradicate West Nile virus, overfishing and environmental changes in the Sound.

Now, however, one cause - water temperature - seems to be emerging as the chief perpetrator, the one that opens the door to the cascade of shell disease, pesticide sensitivity and increased vulnerability to predators attacking a weakened species. At least that's the conclusion reached by Penny Howell, fisheries biologist for the state Department of Environmental Protection, in cooperation with colleagues at the marine sciences department at the University of Connecticut's Avery Point campus in Groton.

When the waters of the Sound and elsewhere in southern New England warm to 68 degrees Fahrenheit, and stay there for two months or more - a condition occurring more frequently with climate change - lobsters, it seem, become chronically distressed. The gills on their undersides flutter rapidly, they don't draw in the oxygen they need from the water and their off-kilter respiration leaves their blood saturated with carbon dioxide. Adding to that, warm water holds less oxygen than colder water, so the lobsters are working harder for less.

"They start to pant, just like a dog," said Howell, showing a slide of data correlating lobster respiration rates and water temperatures during her presentation at the Connecticut Conference on Natural Resources last week at the University of Connecticut in Storrs. "They have no other way of cooling themselves off. This causes respiratory stress."

Her data show an overall trend of warming seas in southern New England since the 1960s, and more extended periods over 68 degrees in the Sound since the '90s. From Cape Cod north, though, the waters have stayed cooler.

"This is not a linear effect," Howell said. "Lobsters are very tolerant (of changing water temperatures) until they can't tolerate it. It's a threshold effect."

Twice as many lobsters, she said, die from causes other than fishing in the sustained warmer waters versus cooler, and those that survive have compromised immunity.

The research is part of Howell's work at the DEP on issues involving management of lobster populations and rules governing the Sound's remaining commercial lobstermen, as the state and East Coast regulators try to figure out how to help this population recover and keep a culturally and economically important, but struggling, fishery alive. There are about 130 full- and part-time commercial lobstermen in Connecticut, down from a high of 707 in 1980. In the late 1990s, just before the die-off, there were 445.

"This is a management program that ran right smack dab into climate issues," Howell said. "There's no good news here."

Lobsters head

for deep water

From sources including annual DEP sampling studies of the Sound, called trawl surveys, as well as thermometers attached to the traps of commercial lobstermen, Howell has determined that lobsters are surviving in the deepest waters of the Sound, where temperatures are likely to stay colder.

"In the 1980s we used to catch them in less than 30 feet," she said. Now, it's rare to find them in depths less than 90 feet.

"We've looked at the commercial catch, and it tells the same kind of story."

In the Sound, the deepest areas lie mainly in an east-west band across the center, although also in this region's waters of the eastern end and The Race. These have the added benefit of being cleaner than the western end due to more tidal flushing from the ocean and lack of the hypoxic, or oxygen-poor, conditions found in the western Sound.

These deeper waters, Howell said, are serving as refuges for the surviving lobsters, and she hopes a viable population will be able to hang on there until future generations have emerged with a greater tolerance for warm water.

"These animals can adapt, as long as things don't happen too fast," she said. "The problem is, we don't know how fast is too fast."

If recovery is possible, it won't be swift, her findings suggest, adding further information to persuade fisheries regulators that the already reduced commercial fishery must endure more catch limits if the lobster population is to survive.

New quotas possible

On March 21, the Atlantic States Marine Fisheries Commission's Lobster Management Board, a multi-state panel, will meet to consider new rules that would cut the current harvest south of Cape Cod by up to half or more, and could also curtail the season for the now year-round fishery. These measures are only slightly less drastic than the main proposal on the table last year - a five-year closure of the fishery - that now appears less likely to be adopted.

"It's the reduction the board feels is necessary," said Toni Kerns, senior fisheries management plan coordinator for the board. "If the environmental conditions don't change, yes, this will be a long-term issue."

A final decision is not likely to be made at the March meeting, she said. If the board agrees on a proposed action, public hearings and more meetings will follow until a final decision is made, possibly by the end of the year.

"There are legal regulatory demands, so we have to do something," said Nancy Balcom, associate director of Connecticut Sea Grant, based at Avery Point. "We thought by now we would have seen a recovery. We know this is hard for the fishermen to know so many things are against them."

Both she and Howell would like to see the research continue, to incorporate the effects of areas with low oxygen, factor in the effects of Connecticut River outflow on water temperature and accurately map the refuge areas with viable habitat. Howell would also like to determine what effect the warm water periods are having on reproduction, because it appears that either lobsters are laying fewer eggs, or the young are not surviving.

Lobstermen dispute findings

The seemingly inevitable direction in which the Atlantic States board is taking the fishery, however long it takes, leaves local lobstermen Mike Theiler of Waterford, Ray Konikowski of Norwich and Michael Grimshaw of Stonington frustrated and angry, as the chances of their long-term survival in their chosen careers seem to grow ever smaller.

For Theiler, who keeps his vessel at State Pier in New London, this isn't about a stressed natural resource, but rather jobs and economics. He questions Howell's research and conclusions, asserting that, "there have been other warm water periods. Water temperature has an effect, but not as extreme (as her findings indicate). Lobsters in this area are used to warm water. They move around.

"What the DEP is doing is drawing conclusions and trying to find the data to back it up," said Theiler, who is head of the Connecticut Commercial Lobstermen's Association.

The association, he said, will tell the regional fisheries board that any further effort to curtail the southern New England fishery would effectively kill it, meaning devastating losses for the fishermen from their investments in vessels, gear and knowledge of their trade and the waters of the Sound. His profits have been cut repeatedly in recent years by increases in the minimum legal size for lobsters, required widening of escape vents on traps and other measures.

"My margins now are only 10 to 15 percent," he said. "I have two crew on my boat, so that means this boat supports three families, and that doesn't include the fuel guy, the bait guy and the restaurants (that buy the lobsters). How are we going to replace those jobs?"

In his view, the regulators should back off and let the fishery find its own sustainable level. If the lobsters aren't there, fishermen will stop on their own - fuel and bait are too costly these days to make a paltry haul worthwhile.

"We'd be better off with less regulation," he said. "We're guys who just want to work. We don't want handouts."

Konikowski, who fishes with his wife, Jean, out of Groton, also questions whether the data being used by regulators is really giving an accurate picture of the fishery. He began lobstering 20 years ago, after the commercial fishery for striped bass was shut down due to overfishing.

"I got shut out of one fishery, and I invested $150,000 to get into this," said Konikowski, who is 68 years old. "It's very frustrating. I really believe they want to put everybody out of business."

These days, he said, up to half of the lobsters that end up in the 400 to 550 traps he has out at any one time end up getting thrown back for not meeting the legal size.

"And 85 to 90 percent of the ones we throw back would have made it under the last gauge size," he said.

Grimshaw said he doesn't think the regulators have given the legal size increases and other measures enough time to spur the population's recovery. Before they take steps that would effectively shut the fishery, he said, they should give more consideration to how the fishermen would be hurt.

"They might as well give us a five-year ban and pay us to stay home, like they do the farmers," said Grimshaw, who is president of the Southern New England Fishermen and Lobstermen's Association. "We're the ones bearing the brunt of the recovery efforts, as far as how they're going to rectify it."

Howell said she's hoping in the future to do cooperative studies with the commercial lobsterman who are able to hang on, to collect more information about the population and how it might be helped to rebuild. She stressed that while further reductions in the fishery appear necessary, lobstermen are not being blamed for the state of the population.

"It's not their fault, but the stocks are in deep trouble, and in order to keep it in viable shape we have to cut back," she said.


Estimated lobster abundance

North of Cape Cod:
107 million legal-sized lobsters
Healthy threshold: 72 million legal-sized lobsters
(Excluding Georges Bank)

South of Cape Cod:
14 million legal-sized lobsters
1996: 37 million legal-sized lobsters
Healthy threshold: 20 million legal-sized lobsters


Loading comments...
Hide Comments