Climate change and climate variability are affecting marine mammal species and these impacts are projected to continue in the coming decades. Vulnerability assessments provide a framework for evaluating climate impacts over a broad range of species using currently available information. We conducted a trait-based climate vulnerability assessment using expert elicitation for 108 marine mammal stocks and stock groups in the western North Atlantic, Gulf of Mexico, and Caribbean Sea. Our approach combined the exposure (projected change in environmental conditions) and sensitivity (ability to tolerate and adapt to changing conditions) of marine mammal stocks to estimate vulnerability to climate change, and categorize stocks with a vulnerability index. The climate vulnerability score was very high for 44% (n = 47) of these stocks, high for 29% (n = 31), moderate for 20% (n = 22), and low for 7% (n = 8). The majority of stocks (n = 78; 72%) scored very high exposure, whereas 24% (n = 26) scored high, and 4% (n = 4) scored moderate. The sensitivity score was very high for 33% (n = 36) of these stocks, high for 18% (n = 19), moderate for 34% (n = 37), and low for 15% (n = 16). Vulnerability results were summarized for stocks in five taxonomic groups: pinnipeds (n = 4; 25% high, 75% moderate), mysticetes (n = 7; 29% very high, 57% high, 14% moderate), ziphiids (n = 8; 13% very high, 50% high, 38% moderate), delphinids (n = 84; 52% very high, 23% high, 15% moderate, 10% low), and other odontocetes (n = 5; 60% high, 40% moderate). Factors including temperature, ocean pH, and dissolved oxygen were the primary drivers of high climate exposure, with effects mediated through prey and habitat parameters. We quantified sources of uncertainty by bootstrapping vulnerability scores, conducting leave-one-out analyses of individual attributes and individual scorers, and through scoring data quality for each attribute. These results provide information for researchers, managers, and the public on marine mammal responses to climate change to enhance the development of more effective marine mammal management, restoration, and conservation activities that address current and future environmental variation and biological responses due to climate change.
Continue reading ‘Vulnerability to climate change of United States marine mammal stocks in the western North Atlantic, Gulf of Mexico, and Caribbean’Posts Tagged 'mammals'
Vulnerability to climate change of United States marine mammal stocks in the western North Atlantic, Gulf of Mexico, and Caribbean
Published 3 October 2023 Science ClosedTags: adaptation, biological response, mammals, methods, otherprocess, performance, review
Climate change vulnerability of cetaceans in Macaronesia: insights from a trait-based assessment
Published 30 September 2021 Science ClosedTags: mammals, North Atlantic, policy
Highlights
- A climate vulnerability assessment was applied to cetaceans in Macaronesia
- Very High to High vulnerability scores for 62% of species management units
- Very High to Moderate certainty scores for 67% of units
- High potential for climate-related responses for over 50% of units
- Further research on trait-based approaches is needed to support decision-makers
Abstract
Over the last decades global warming has caused an increase in ocean temperature, acidification and oxygen loss which has led to changes in nutrient cycling and primary production affecting marine species at multiple trophic levels. While knowledge about the impacts of climate change in cetacean’s species is still scarce, practitioners and policymakers need information about the species at risk to guide the implementation of conservation measures.
To assess cetacean’s vulnerability to climate change in the biogeographic region of Macaronesia, we adapted the Marine Mammal Climate Vulnerability Assessment (MMCVA) method and applied it to 21 species management units using an expert elicitation approach.
Results showed that over half (62%) of the units assessed presented Very High (5 units) or High (8 units) vulnerability scores. Very High vulnerability scores were found in archipelago associated units of short-finned pilot whales (Globicephala macrorhynchus) and common bottlenose dolphins (Tursiops truncatus), namely in the Canary Islands and Madeira, as well as Risso’s dolphins (Grampus griseus) in the Canary Islands. Overall, certainty scores ranged from Very High to Moderate for 67% of units.
Over 50% of units showed a high potential for distribution, abundance and phenology changes as a response to climate change.
With this study we target current and future information needs of conservation managers in the region, and guide research and monitoring efforts, while contributing to the improvement and validation of trait-based vulnerability approaches under a changing climate.
Continue reading ‘Climate change vulnerability of cetaceans in Macaronesia: insights from a trait-based assessment’Chapter 13 – the future of Atlantic walrus in a rapidly warming Arctic
Published 28 June 2021 Science ClosedTags: Arctic, biological response, mammals, mortality, review
The walrus (Odobenus rosmarus) is classified as a focal ecosystem component of the Arctic, defined as a biological element that is considered central to the functioning of an ecosystem, is of major importance to Arctic residents and/or is likely to be a good proxy for short- and long-term changes in the environment. The Arctic is undergoing large-scale environmental changes due to rapid global warming, including a marked reduction of sea ice in several areas inhabited by walruses. This chapter reviews how walruses already have been affected by global warming, or likely will be in the future. Specifically, we review the effects on walruses of projected changes in sea ice cover, marine productivity, ocean acidification, predation, pathogens and ultraviolet radiation, whereas changes in human activity patterns are discussed elsewhere in this volume. We find that, while the Pacific walrus seems to experience negative effects of warming and decrease in sea ice, the Atlantic walruses may be less affected; also in comparison to other ice-associated pinnipeds. Hence, we concur with previous assessments that the walrus is likely to survive into the future; at least in areas where human disturbance is minimal, and suitable terrestrial haul-outs are close enough to their feeding grounds.
Continue reading ‘Chapter 13 – the future of Atlantic walrus in a rapidly warming Arctic’

