How will a warming Arctic affect the Atlantic lobster fishery?
The Arctic is warming rapidly, but what happens in the Arctic may not stay there; lobster populations and lobster-dependent communities further south may also be affected. This will be the focus of a new multi-institutional study at the University of Maine, Columbia Climate School and other institutions.
Building on longstanding partnerships with fisheries and governments, the team will investigate how changes in the Arctic are altering lobster populations and distribution from the coast of Rhode Island to Newfoundland. Richard Wahle, director of the Lobster Institute at the University of Maine, is leading the project.Columbia research team led by oceanographer joking go of Lamont-Doherty Earth Observatory, who conceived the project based on new findings that ice melt is causing freshening and changes in ocean circulation patterns in the subarctic Atlantic.
The National Science Foundation is funding the $3 million project as one of its 10 big ideas. The project will support investigations into the impacts of past and future climate change and management practices. The results could help improve lobster population and distribution forecasts and increase understanding of the economics of an industry that will net Maine $725 million in 2021. Researchers say they hope new data on Arctic ice melting trends will give them and fishermen an unprecedented amount of time to predict ecosystem changes.
Since 2000, lobster populations (marked in red) have moved northward along the coasts of New England and southern Canada, and the impact of the warmer Gulf Stream (white) has also increased. (courtesy of Joaquim Goes)
A warming Arctic poses multiple threats to the world’s oceans. Melting glaciers, icebergs and ice sheets are increasing sea levels. They are also altering ocean circulation, an important driver of global thermal motion that, when disturbed, raises or lowers water temperatures and leads to unpredictable weather and climate change.
The researchers’ goal is to use the latest information and models on changing Arctic conditions to predict how ocean circulation and coastal ecosystems in the Northwest Atlantic will change by 2050. In turn, this information will be used to update and expand existing models of juvenile lobster transport and populations. Economists will use this information to assess the impact on fishing fleet operations. Social scientists will build on the resilience indicators already developed for Maine and extend their scope to communities in other parts of New England and Atlantic Canada.
Previous research has shown that there are winners and losers in warming oceans when it comes to lobster fisheries. Rising temperatures in the Gulf of Maine, for example, are warming faster than most of the world’s ocean waters, causing lobsters to move farther north to keep up with their usual cold-water habitats. The lobster fishery in southern New England has experienced significant mortality and economic loss. At the same time, rising temperatures over the past few decades have had beneficial effects in far north, although continued warming now could threaten the long-term viability of fisheries.
Just as the influence of the cold, nutrient-rich Labrador Current from the north is waning, the influence of the warmer, saline and nutrient-poor Gulf Stream waters is becoming stronger, dramatically altering the productivity of Gulf of Maine ecosystems. The researchers speculate that these changes, as well as the adverse effects of the stress of warm summers, resulted in decreased survival of juvenile lobsters and ultimately reduced production.
The research is also relevant to understanding changes in the abundance and distribution of other members of the ecosystem, from the smallest plankton to the iconic Atlantic cod, herring, and even the endangered North Atlantic right whale.
“The lobster fishery is a traditional industry that is vital to Maine’s island and coastal communities,” said Marianne LaCroix, executive director of the Maine Lobster Marketing Partnership. “Learning more about future climate conditions [will] Allow fisheries to adjust practices so they can see continued success. “
The project also includes researchers from the Gulf of Maine Institute, Florida State University and Memorial University of Newfoundland. Other members of the Colombian Climate Schools team are Helga do Rosario Gomes, Marco Tedesco and Patrick Alexander.
Adapted from a University of Maine press release.
