ELLSWORTH — Warming ocean waters will have a big impact on Maine’s $547 million lobster industry in coming years, but the future would look a lot bleaker if not for the conservation efforts of the state’s thousands of lobster fishermen.
According to a study led by scientists at the Gulf of Maine Research Institute, the University of Maine and NOAA Fisheries, conservation practices long advocated by Maine lobstermen are helping make the lobster fishery more resilient to climate change.
For generations, lobstermen in Maine have returned large lobsters and egg-bearing female lobsters to the water rather than keeping them. Lobstermen first marked the tails of the egg bearers with a distinctive “V-notch” to give them further protection.
According to the scientists, these conservation practices, developed by custom and now mandated by state law, distinguish the fishery in the Gulf of Maine, where Maine harvesters trap some 83 percent of all lobster landings, from southern New England, where fishermen historically refused to take the same steps to preserve large, reproductive lobsters.
Funded by the National Science Foundation and published this week in the Proceedings of the National Academy of Sciences, the study shows how warming waters and contrasting conservation practices have contributed to significantly different results in the two fisheries.
Over the past decade (at least until this past year), Maine lobster landings have climbed steadily, setting new records nearly every year. During the same time period, the southern New England lobster population, and lobster fishery, has collapsed.
According to figures compiled by regulators, the commercial lobster landings in Connecticut fell from more than 2.5 million pounds in 1995 to about 200,000 pounds in 2015. In Rhode Island, the catch fell from more than 5 million pounds in 1995 to less than 2.4 million pounds in 2015. In New York, the commercial lobster industry has virtually disappeared.
Led by Arnault Le Bris of the Gulf of Maine Research Institute, the scientists used advanced computer models to simulate the ecosystem under varying conditions. The results show that temperature change was the primary contributor to population changes, but conservation efforts made significant differences in how the lobster population responded.
The study concluded that in the Gulf of Maine, the lobster fishery is vulnerable to future temperature increases. As the water continues to warm, the lobster population is likely to shift farther north and eastward, off Canada, where the waters are likely to remain cooler.
Though that could bode ill for the future of Maine’s lobster fishery, the scientists say, continued conservation efforts can mitigate the impacts of future warming. Over the next 30 years, as long as conservation practices continue, the researchers anticipate average populations similar to those in the early 2000s.
During the first half of that decade, Maine lobster landings averaged about 61.5 million pounds, less than half the roughly 131 million pounds, the all-time record, landed in 2016.