The 2020 American Lobster Benchmark Stock Assessment was released in November by the Atlantic States Marine Fisheries Commission. The study, undertaken every five years, presents contrasting results for the two American lobster stock units, with record high abundance and recruitment in the Gulf of Maine and Georges Bank stock (GOM/GBK) and record low abundance and recruitment in the Southern New England stock (SNE) in recent years. The SNE stock is significantly depleted with poor prospects of recovery.
Stock status was assessed using the University of Maine Stock Assessment Model for American Lobster, a statistical catch-at-length model that tracks the population of lobster by sex, size and season over time. Southern New England lobster stocks, once robust, have declined to record lows in recent years according to scientists and regulators. The assessment found that lobster populations in southern New England have reached their lowest levels on record.
While past assessments have shown a decline in southern New England lobster stocks since the late 1990s, the 2020 report is particularly dire, predicting that the fishery is unlikely to recover as abundance dips below thresholds required to maintain population. Even more troubling, scientists said, was that lobster stocks did not show signs of overfishing, signaling that the cause of the rapid and drastic population decline is likely a combination of environmental factors, including warming water temperatures and increased shell disease that have created unfavorable conditions for the species.
“Extensive research has highlighted the influence of the environment on American lobster life history and population dynamics. Among the critical environmental variables, temperature stands out as the primary influence. Further, its range is experiencing changing environmental conditions at some of the fastest rates in the world. Therefore, considering these environmental influences is vital when assessing the lobster stocks and was a focal point of this stock assessment,” the ASFMC said in a statement.
American fishermen caught more than 126 million pounds of lobster last year. More than 100 million of those pounds came to the docks in Maine. The annual southern New England catch in 2018 was only 2.7 million pounds — about 2% of total U.S. lobster landings.