How Will a Warming Arctic Affect the Atlantic Lobster Fishery?
The Arctic is rapidly warming, but what happens in the Arctic may not stay there; lobster populations and the communities that depend on them much farther south may also be affected. This will be the focus of a new multi-institutional study by the University of Maine, Columbia Climate School and other institutions.
Building on long-standing partnerships with the fishing industry and government, the team will investigate how Arctic change alters lobster abundance and distribution from coastal Rhode Island to Newfoundland. Richard Wahle, director of the University of Maine Lobster Institute, is spearheading the project. The Columbia research team is led by oceanographer Joaquim Goes of Lamont-Doherty Earth Observatory, who conceived the project based on new findings of ice-melt induced freshening of the sub-Arctic Atlantic and changing ocean circulation patterns.
The U.S. National Science Foundation is funding the $3 million project as one of its 10 Big Ideas. The project will support investigations into the influence of past and future climate changes and management practices. The results could help improve lobster population and distribution forecasts, and increase understanding of the economics of an industry that netted $725 million in 2021 in Maine alone. The researchers say they hope that new data on Arctic ice melt trends will give them and fishermen unprecedented lead time to anticipate ecosystem changes.
Since 2000, lobster populations (red markers) have moved north along the coasts of New England and southern Canada, and the influence of the warm Gulf Stream current (white) has increased. (Courtesy Joaquim Goes)
Arctic warming poses several threats to the world’s oceans. Melting glaciers, icebergs and ice sheets are increasing sea levels. They are also altering ocean circulation, a crucial driver of heat movement around the globe that, when disrupted, can increase or decrease water temperatures and cause unpredictable weather and climatic changes.
The researchers aim to use the latest information and models of changing Arctic conditions to generate forecasts on how ocean circulation and the coastal ecosystem of the Northwest Atlantic will change out to 2050. In turn, this information will be used to update and geographically expand existing models of larval lobster transport and populations. Economists will use this information to evaluate impacts on fishing fleet operations. Social scientists will build on resilience indicators already under development for Maine, and expand their reach to communities in other parts of New England and Atlantic Canada.
Previous research has shown that when it comes to the lobster fishery, there are winners and losers in a warming ocean. For example, rising temperatures across the Gulf of Maine, which is warming faster than the vast majority of the world’s ocean waters, have caused lobsters to shift farther north to keep pace with their customary cold-water habitat. Lobster fisheries in southern New England have experienced significant die-offs and financial loss. At the same time, rising temperatures have had favorable effects in more northerly areas over past decades, although continued warming now may threaten the fishery’s long-term viability.
Just as the influence of the cold, nutrient-rich Labrador Current from the north is diminishing, the warm, salty and nutrient-poor Gulf Stream waters are being felt more strongly, dramatically altering the productivity of the Gulf of Maine ecosystem. Researchers hypothesize that these changes, along with the adverse effects of stressful warm summer temperatures, have caused a decline in larval lobster survival that ultimately results in smaller harvests.
The research is also relevant to understanding the changing abundance and distribution of other members of the ecosystem, from the tiniest plankton to the iconic Atlantic cod, herring and even the endangered North Atlantic right whale.
“The lobster fishery is a heritage industry that is essential to the island and coastal communities of Maine,” says Marianne LaCroix, executive director of the Maine Lobster Marketing Collaborative. “Knowing more about future climate conditions [will] allow the fishery to adapt practices so that they can see continued success.”
The project also includes researchers from the Gulf of Maine Research Institute, Florida State University and Memorial University of Newfoundland. The other members of the Columbia Climate School team are Helga do Rosario Gomes, Marco Tedesco and Patrick Alexander.
Adapted from a press release by the University of Maine.
