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1. Suitability of foraging habitat for Eubalaena glacialis under future climate scenarios in the Northwest Atlantic

   https://doi.org/10.1525/elementa.2024.00044  

   Johnson, Omi H; Plourde, Stéphane; Lehoux, Caroline; Ross, Camille H; Tupper, Benjamin; Orphanides, Christopher D; Walsh, Harvey J; Record, Nicholas R (May 2025, Elem Sci Anth)

   The critically endangered North Atlantic right whale (Eubalaena glacialis) faces significant anthropogenic mortality. Recent climatic shifts in traditional habitats have caused abrupt changes in right whale distributions, challenging traditional conservation strategies. Tools that can help anticipate new areas where E. glacialis might forage could inform proactive management. In this study, we trained boosted regression tree algorithms with fine-resolution modeled environmental covariates to build prey copepod (Calanus) species-specific models of historical and future distributions of E. glacialis foraging habitat on the Northwest Atlantic Shelf, from the Mid-Atlantic Bight to the Labrador Shelf. We determined foraging suitability using E. glacialis foraging thresholds for Calanus spp. adjusted by a bathymetry-dependent bioenergetic correction factor based on known foraging behavior constraints. Models were then projected to 2046–2065 and 2066–2085 modeled climatologies for representative concentration pathway scenarios RCP 4.5 and RCP 8.5 with the goal of identifying potential shifts in foraging habitat. The models had generally high performance (area under the receiver operating characteristic curve > 0.9) and indicated ocean bottom conditions and bathymetry as important covariates. Historical (1990–2015) projections aligned with known areas of high foraging habitat suitability as well as potential suitable areas on the Labrador Shelf. Future projections suggested that the suitability of potential foraging habitat would decrease in parts of the Gulf of Maine and southwestern Gulf of Saint Lawrence, while potential habitat would be maintained or improved on the western Scotian Shelf, in the Bay of Fundy, on the Newfoundland and Labrador shelves, and at some locations along the continental shelf breaks. Overall, suitable habitat is projected to decline. Directing some survey efforts toward emerging potential foraging habitats can enable conservation management to anticipate the type of distribution shifts that have led to high mortality in the past. 

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2. Exploring movement patterns and changing distributions of baleen whales in the western North Atlantic using a decade of passive acoustic data

   https://doi.org/10.1111/gcb.15191  

   Davis, Genevieve E.; Baumgartner, Mark F.; Corkeron, Peter J.; Bell, Joel; Berchok, Catherine; Bonnell, Julianne M.; Bort Thornton, Jacqueline; Brault, Solange; Buchanan, Gary A.; Cholewiak, Danielle M.; et al (January 2020, Global Change Biology)

   Six baleen whale species are found in the temperate western North Atlantic Ocean, with limited information existing on the distribution and movement patterns for most. There is mounting evidence of distributional shifts in many species, including marine mammals, likely because of climate-driven changes in ocean temperature and circulation. Previous acoustic studies examined the occurrence of minke (Balaenoptera acutorostrata) and North Atlantic right whales (NARW; Eubalaena glacialis). This study assesses the acoustic presence of humpback (Megaptera novaeangliae), sei (B. borealis), fin (B. physalus), and blue whales (B. musculus) over a decade, based on daily detections of their vocalizations. Data collected from 2004 to 2014 on 281 bottommounted recorders, totaling 35,033 days, were processed using automated detection software and screened for each species' presence. A published study on NARW acoustics revealed significant changes in occurrence patterns between the periods of 2004–2010 and 2011–2014; therefore, these same time periods were examined here. All four species were present from the Southeast United States to Greenland; humpback whales were also present in the Caribbean. All species occurred throughout all regions in the winter, suggesting that baleen whales are widely distributed during these months. Each of the species showed significant changes in acoustic occurrence after 2010. Similar to NARWs, sei whales had higher acoustic occurrence in mid-Atlantic regions after 2010. Fin, blue, and sei whales were more frequently detected in the northern latitudes of the study area after 2010. Despite this general northward shift, all four species were detected less on the Scotian Shelf area after 2010, matching documented shifts in prey availability in this region. A decade of acoustic observations have shown important distributional changes over the range of baleen whales, mirroring known climatic shifts and identifying new habitats that will require further protection from anthropogenic threats like fixed fishing gear, shipping, and noise pollution. 

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3. Ecology and life history of baleen whales inform climate change vulnerabilities and priorities for future monitoring

   https://doi.org/10.1093/icesjms/fsag042  

   Thorne, Lesley H; Meyer-Gutbrod, Erin (March 2026, ICES Journal of Marine Science)

   Baleen whales are key consumers in marine habitats that serve as vectors of nutrients, but their populations have been slow to recover from past commercial whaling due to their low reproductive rates and ongoing anthropogenic threats. Climate impacts have become central to the demography and habitat use of baleen whales, and conservation efforts must account for these impacts to be effective. However, knowledge of baleen whale climate responses is lacking, and current survey effort is insufficient to capture changes in migration and habitat use for many species. Due to their unique combination of ecological and life history characteristics, baleen whales are particularly vulnerable to climate change and their climate responses should be expected to differ fundamentally from those of other marine consumers. These characteristics include the need for both large quantities and high densities of prey, the need to accumulate large energy reserves seasonally, as well as highly migratory movements and the reliance on high-latitude foraging areas with narrow seasonal windows in resource availability. Climate responses in baleen whales may involve abrupt changes in foraging habitat in contrast to more gradual poleward shifts observed in other species, changes in the timing, extent or tendency for migration, and changes in energy accumulation or fitness. Recognizing that climate impacts may differ from other species is critical to measuring and anticipating changes to baleen whale populations in the face of ongoing climate change, and to effectively managing their populations in the future. North Atlantic right whales (Eubalena glacialis), arguably the best studied baleen whale species at a population scale, exemplify expectations for baleen whale climate responses and the implications for future management and conservation. Right whales have shown abrupt changes to traditional patterns of habitat use and migratory behavior, with major implications for the effectiveness of existing protections. Understanding and detecting baleen whale climate responses and effectively guiding management in the face of ongoing change will require increased survey effort and novel methods to survey remote habitats; improved knowledge of mechanisms of prey aggregation and climate impacts on these processes; and continued development and refinement of mechanistic models and dynamic management strategies. 

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4. Climate impacts on the Gulf of Maine ecosystem

   https://doi.org/10.1525/elementa.2020.00076  

   Pershing, Andrew J.; Alexander, Michael A.; Brady, Damian C.; Brickman, David; Curchitser, Enrique N.; Diamond, Antony W.; McClenachan, Loren; Mills, Katherine E.; Nichols, Owen C.; Pendleton, Daniel E.; et al (January 2021, Elementa: Science of the Anthropocene)

   The Gulf of Maine has recently experienced its warmest 5-year period (2015–2020) in the instrumental record. This warming was associated with a decline in the signature subarctic zooplankton species, Calanus finmarchicus. The temperature changes have also led to impacts on commercial species such as Atlantic cod (Gadus morhua) and American lobster (Homarus americanus) and protected species including Atlantic puffins (Fratercula arctica) and northern right whales (Eubalaena glacialis). The recent period also saw a decline in Atlantic herring (Clupea harengus) recruitment and an increase in novel harmful algal species, although these have not been attributed to the recent warming. Here, we use an ensemble of numerical ocean models to characterize expected ocean conditions in the middle of this century. Under the high CO2 emissions scenario (RCP8.5), the average temperature in the Gulf of Maine is expected to increase 1.1°C to 2.4°C relative to the 1976–2005 average. Surface salinity is expected to decrease, leading to enhanced water column stratification. These physical changes are likely to lead to additional declines in subarctic species including C. finmarchicus, American lobster, and Atlantic cod and an increase in temperate species. The ecosystem changes have already impacted human communities through altered delivery of ecosystem services derived from the marine environment. Continued warming is expected to lead to a loss of heritage, changes in culture, and the necessity for adaptation. 

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5. Rapid 20th century warming reverses 900-year cooling in the Gulf of Maine

   https://doi.org/10.1038/s43247-022-00504-8  

   Whitney, Nina M.; Wanamaker, Alan D.; Ummenhofer, Caroline C.; Johnson, Beverly J.; Cresswell-Clay, Nathaniel; Kreutz, Karl J. (December 2022, Communications Earth & Environment)

   Abstract The Gulf of Maine, located in the western North Atlantic, has undergone recent, rapid ocean warming but the lack of long-term, instrumental records hampers the ability to put these significant hydrographic changes into context. Here we present multiple 300-year long geochemical records (oxygen, nitrogen, and previously published radiocarbon isotopes) measured in absolutely-dated Arctica islandica shells from the western Gulf of Maine. These records, in combination with climate model simulations, suggest that the Gulf of Maine underwent a long-term cooling over most of the last 1000 years, driven primarily by volcanic forcing and North Atlantic ocean dynamics. This cooling trend was reversed by warming beginning in the late 1800s, likely due to increased atmospheric greenhouse gas concentrations and changes in western North Atlantic circulation. The climate model simulations suggest that the warming over the last century was more rapid than almost any other 100-year period in the last 1000 years in the region. 

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