The future is uncertain for lobster fishing south of Cape Cod, a top state fisheries biologist told a gathering of lobster fishermen at a conference last weekend.

“It will likely be poor for the foreseeable future,” said Bob Glenn, a senior biologist with the state Division of Marine Fisheries.

He blamed rising water temperatures, not overfishing.

Mr. Glenn was one of several speakers at the Massachusetts Lobstermen’s Association’s gathering held over the weekend at the Sea Crest Beach Hotel in Falmouth. Lobstermen from across the commonwealth attended, including a handful from the Vineyard.

Bernie Feeney, president of Massachusetts Lobstermen's Association: "We have an economic problem, not a resource problem." — Mark Lovewell

Mr. Glenn outlined a lengthy report on the health of lobsters from the Gulf of Maine to waters south of the Vineyard. The report was compiled using data collected from fishermen, from survey work and computer modeling. Dividing the area into three sectors, Mr. Glenn said the Gulf of Maine lobster fishery is holding its own, and he said the fishery east of Cape Cod is also healthy. But his tone changed when describing the lobster fishery south of Cape Cod.

“There are fewer and fewer fishermen,” Mr. Glenn said. “There is very little fishing effort going on compared to what it was historically . . . [but] those that are still fishing are catching reasonable rates.”

Emerging data on spawning lobsters from Buzzards Bay shows a troubling decline in numbers since 2008. With summer water temperatures on the rise, many of the juvenile lobsters will not survive, Mr. Glenn said.

As for inshore lobsters, “The stock has declined to almost nonexistent levels,” Mr. Glenn said. “There are some . . . south of Rhode Island.”

He said lobsters become stressed in water temperatures above 68 degrees.

Mr. Glenn said lobsters historically laid their eggs in Buzzards Bay in the summer months, and the juveniles would later congregate on the rocky bottom inshore. But with water temperatures now above what lobsters can tolerate, instead of going into the bay, female lobsters are now laying their eggs farther south, off Nomans Land. And those eggs have zero chance of making their way into Buzzards Bay, the biologist said.

Other conference sessions covered a variety of topics.

Bernie Feeney, president of the 51-year-old association, said the industry will need to adapt in order to remain financially viable. He led a brief forum on changes in the lobster industry. He operates a 40-foot lobster boat out of Boston Harbor (the Sandra Jean), and said he has fished since 1978.

With prices flat and the cost of doing business on the rise, he said it’s tough to make a living from lobstering.

“The margin gets smaller,” he said. “We have an economic problem, not a resource problem.”

Dan McKiernan, deputy director of the state Division of Marine Fisheries, said fishermen who retire their fishing licenses are surrendering the number of pots they can put out. Attrition, the number of lobstermen fishing, and the decline in licenses are expected to continue.

One session concerned the future relationship between lobstermen and wind farms.

John Williamson, a marine fisheries consultant from Kennebunk, Me., reported on a four-day trip he took to England to meet wind farm developers and affected fishermen. The trip was sponsored by the Ocean Conservancy. They toured the waters around wind farms comparable in size to the proposed Cape Wind project for Nantucket Sound.

He urged fishermen to pay attention and get involved in the development process. He said fishermen know the waters and can have an impact in the design and layout of wind farms.