Due to a combination of climate change creating warmer water conditions and continued pressure from fishing, lobster stocks in southern New England have been badly depleted, and a five-year moratorium is needed for recovery.

This is the recommendation of a technical panel for the Atlantic States Marine Fisheries Commission in a report discussed last week.

“Overwhelming environmental and biological changes coupled with continued fishing greatly reduce the likelihood of southern New England stock rebuilding,” the report said.

Robert Glenn, senior fisheries biologist for the state Division of Marine Fisheries and a state expert on lobsters, spoke at an informational meeting at the University of Massachusetts at South Dartmouth last Thursday. More than 60 lobstermen attended. If it is approved, the moratorium would take effect in July of 2011 from the southern New England coast to Virginia, for both commercial and recreational lobster fishing.

Word of the proposed moratorium reached the Menemsha waterfront over the weekend. Stephen Larsen, a Menemsha lobsterman since 1974, said a fishing ban would have a devastating impact. “It would put us out of business. We all have mortgages,” he said. Mr. Larsen said he and other Menemsha fishermen are already struggling to earn a living.

Statistics in the report from the technical committee paint a stark picture of a fishery in steep decline.

The lobster fishery is the second biggest income producer in the state at the dock, second only to offshore sea scalloping. In 1999 Massachusetts lobstermen landed 15.8 million pounds of lobsters. Since then the number has dropped to 10.9 million pounds. Most lobsters landed in the state now are fished north of Cape Cod, the report shows.

Last year Buzzards Bay and Vineyard Sound lobstermen landed 176,728 pounds, a small fraction compared with 1989 when they landed over a million pounds, and in 1999 when they landed just under 900,000 pounds.

In an interview last week, Dan McKiernan, state deputy director for the Division of Marine Fisheries, said: “We’ve known for some time, from fishermen’s anecdotes and science, that the southern New England lobster fishery is in decline. There has been a lot of attrition in the fishery. Those few guys that are still in the fishery may still be seeing some decent landings.

“But what is striking is that there is new information that suggests that down the pipeline there are some weak year classes ahead, and that will bring the fishery down to its knees four to seven years from now.”

Surveys, including an examination of currents using satellite technology, have been conducted to find the youngest lobsters and also to pinpoint populations of female, egg-bearing lobsters.

Mr. Glenn said the surveys show there are no egg-bearing lobsters in Buzzards Bay. Instead, scientists are finding female egg-bearing lobsters in deeper, colder water to the south and south of Noman’s Land.

The information is significant because it means free-swimming lobster larva will no longer find their way to Rhode Island and Massachusetts inshore waters. Currents south of Noman’s Land will carry the larva toward Long Island and into areas that are considered poor lobster habitat.

The report found that warming water temperatures are almost certainly more than coincidental. “It is not possible to draw a direct relationship between the decline of the southern New England lobster stock and increased water temperatures,” the report said. “However, the strong coincidence in the timing of the increase in water temperature with the timing of the decline in landings, spawning stock biomass, and recruitment, coupled with overwhelming experimental evidence of increased physiological stress, immunosupression, and increased rates of disease in lobster exposed to prolonged periods of water over 20 degrees Celsius, strongly suggest that increasing water temperatures have played a primary role.”

Atlantic lobster landings have plummeted as far south as Virginia.

The Atlantic States Marine Fisheries Commission lobster technical committee includes nine biologists, all from the East Coast, as well as a biologist from the National Marine Fisheries Service.

Mr. Glenn, a member of the committee, said the findings in the report have been difficult to consider, even for the biologists involved in the work.

“Our most recent meeting was in March. It was very somber. We were asked to review the current status and provide recommendations. It wasn’t until we really looked at the recent data from 2009, and looked at the juvenile settlement of lobsters that we saw the magnitude of the crisis,” he said.

He said the committee is often divided and usually reaches decisions through consensus. But this time he said the group was unanimous in its recommendation that a moratorium be enacted. The purpose of the moratorium, would be to “give one generation of lobsters an opportunity to reproduce without any commercial exploitation. It would try and preserve what spawning stock there is left,” he said, adding:

“From my standpoint, we are not managers. I don’t make manager decisions. We’ve given our advice.”

Mr. McKiernan said it will now be up to the commission to decide the next step. “This is one recommendation. The commission has to wrestle with how to execute this, come up with some kind of conservation strategy, to minimize the impact on the fishermen,” he said.

The report also noted that a moratorium would improve the chances for fishermen to obtain federal relief money.

But Bill Adler, executive director of the Massachusetts Lobster Association, said lobstermen will be up in arms against any ban on fishing. Mr. Adler is a voting member of the Atlantic States Marine Fisheries Commission. “I knew what was coming,” he said, adding: “Remember, they said that it is not the fishermen causing the problem, it is the temperature, it is predation, it is water quality, it is all those factors causing the problem. Even if they shut down the fishing, there is no guarantee. The stock is depleted, but they are not overfishing. I am totally opposed to any moratorium.”

The commission will hold a special meeting to discuss the crisis in the lobster fishery on July 22 in Providence, R.I. If a moratorium is formally proposed by the commission, public hearings would be held later in the year.

For Ray Gale, a Tisbury commercial fisherman who has shifted away from lobstering as his primary income in recent years, the idea of a ban stirred emotion. “I love to go lobster fishing. I have mixed feelings. If there was a moratorium, it would make me cry,” he said yesterday.

But John Hughes, 88, a retired biologist and lobster expert who ran the state lobster hatchery in Oak Bluffs from 1948 to 1984, said a moratorium may simply be an exercise in futility. “It is a wonderful thing, what they are doing. They stuck their chin out,” he said. “Biologically it is a great idea, great for the lobster populations. But from a social and economic standpoint, it won’t fly.”