UMaine leads study on how warming Arctic affects lobster in New England, Canada
Investigating how a rapidly warming Arctic will affect American lobster populations and the communities that depend on them in New England and Atlantic Canada will be the focus of a University of Maine-led study backed by a $3 million award from the National Science Foundation’s Navigating the New Arctic Program (NNA).
Richard Wahle, director of the university’s Lobster Institute and professor in the School of Marine Sciences, is spearheading the project, dubbed the NNA Lobster Network, joined by 18 other researchers from UMaine, the Gulf of Maine Research Institute, Columbia University, Florida State University and Memorial University of Newfoundland.
The team will investigate how climate-induced Arctic change alters lobster abundance and distribution from coastal Rhode Island to Newfoundland.
The NNA Lobster Network will support investigations into the influence of past and future climate and management scenarios on various physical, biological and socio-economic conditions at different scales; all through cross-sector and cross-border partnerships.
The results of this project could help improve models for lobster population distribution forecasts, as well an understanding of the economic dependence of coastal communities on this fishery and, therefore, their vulnerability to future change, according to a UMaine news release.
Researchers hope that new data on Arctic ice melt will give the team unprecedented lead time to anticipate ocean ecosystem changes that influence lobster distribution and abundance.
Resulting forecasts and scenario analysis tools will provide crucial information for fishermen and other stakeholders in this iconic fishing industry that netted $725 million in 2021 in Maine alone, according to Maine’s Department of Marine Resources.
UMaine faculty involved in the study include Damian Brady, associate professor of oceanography; Christine Beitl, associate professor of anthropology; Joshua Stoll, assistant professor of marine policy; and Heather Leslie, professor of marine sciences and director of the Darling Marine Center. Outreach and communication staff support is provided by Chris Cash, assistant director of the Lobster Institute; Natalie Springuel, Marine Extension program leader with Maine Sea Grant; and a technical liaison yet to be hired. The project also includes four postdoctoral fellows and two graduate students.
Melting glaciers, icebergs and ice sheets are increasing sea levels and 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. Additionally, thawing permafrost in the Arctic is releasing more carbon into the atmosphere.
The NNA Lobster Network aims to use the latest information and models of changing Arctic conditions to generate forecasts on how ocean circulation and the lower latitude coastal marine ecosystem of the Northwest Atlantic will change in future decades out to 2050.
In turn, this information will be used to update and geographically expand existing larval lobster transport and population dynamic models initially developed for the Gulf of Maine. In the end-to-end analysis, economists will use this information to evaluate impacts of changes in the lobster resource on fishing fleet dynamics, operations and economic outcomes for the fishery. Project social scientists will build on quantitative climate resilience indicators that are already under development for Maine and expand their reach to lobster communities in other parts of New England and Atlantic Canada.
Previous research by scientists from UMaine and other institutions have discovered that when it comes to the lobster fishery, there are winners and losers in a warming ocean, Wahle said. For example, rising temperatures across the Gulf of Maine, which is warming faster than the vast majority of the world’s oceans, caused lobsters to shift farther north over the years to keep pace with their northerly migrating cold-water habitat.
As a result, lobster fisheries in southern New England have experienced significant die-offs and financial loss. At the same time, rising temperatures have had favorable effects on the Gulf of Maine’s lobster fishery over the past decades, although continued warming now may threaten its 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, altering the productivity of the Gulf of Maine ecosystem.
Researchers hypothesized that these climate-induced ecosystem changes, along with the adverse effects of stressfully warm summer temperatures, have caused a decline in larval lobster survival that ultimately results in smaller harvests.
This work is also relevant to understanding the changing abundance and distribution of members of the ecosystem other than the lobster, from the tiniest plankton to the iconic Atlantic cod, herring and even the endangered North Atlantic right whale.
To determine how changes in the Arctic affect lobster populations in the Northwest Atlantic, Wahle and his team plan to create a climate vulnerability assessment that focuses on the lobster fishery’s northward range shift as the ocean warms. They also will develop a coupled atmosphere-ice-ocean-ecosystem model to examine how changes in ocean circulation and the Arctic cryosphere, the frozen parts of the region, affect fishery and ecosystem productivity in New England and Atlantic Canada. Researchers will use existing field datasets, including some co-produced with the fishing industry, to validate their model.