The lobster population has crashed to the lowest levels on record in southern New England while climbing to heights never before seen in the cold waters off Maine and other northern reaches—a geographic shift that scientists attribute in large part to the warming of the ocean. In 2013, the number of adult lobsters in New England south of Cape Cod slid to about 10 million, just one-fifth the total in the late 1990s, according to a report issued this month by regulators. The lobster catch in the region sank to about 3.3 million pounds in 2013, from a peak of about 22 million in 1997. The declines are "largely in response to adverse environmental conditions, including increasing water temperatures over the last 15 years" and continued fishing, said the Atlantic States Marine Fisheries Commission.
At a power plant in Long Island Sound, for example, there were more than 75 days with a recorded average water temperature above 68 degrees Fahrenheit in 2012, 2013, and 2014, the report said. Between 1976 and 2010, that happened only twice. In northern New England, meanwhile, lobsters are booming. The population in the Gulf of Maine—a body of water that touches Canada, Maine, New Hampshire, and the northern shore of Massachusetts—and in the Georges Bank fishing grounds farther out to sea has reached record highs, more than doubling to about 250 million adult lobsters since the mid-1990s, the report said. "It very much looks like what you would expect from a species that is responding to a warming ocean—it's going to move toward the poles," says the chief scientific officer for the Gulf of Maine Research Institute of Portland, Maine.