Marine mammal hotspots across the circumpolar Arctic

Abstract

Aim: Identify hotspots and areas of high species richness for Arctic marine mammals.Location: Circumpolar Arctic.Methods: A total of 2115 biologging devices were deployed on marine mammals from 13 species in the Arctic from 2005 to 2019. Getis-Ord G i * hotspots were calculated based on the number of individuals in grid cells for each species and for phylogenetic groups (nine pinnipeds, three cetaceans, all species) and areas with high species richness were identified for summer (Jun-Nov), winter (Dec-May) and the entire year. Seasonal habitat differences among species' hotspots were investigated using Principal Component Analysis.Results: Hotspots and areas with high species richness occurred within the Arctic continental-shelf seas and within the marginal ice zone, particularly in the "Arctic gateways" of the north Atlantic and Pacific oceans. Summer hotspots were generally found further north than winter hotspots, but there were exceptions to this pattern, including bowhead whales in the Greenland-Barents Seas and species with coastal distributions in Svalbard, Norway and East Greenland. Areas with high species richness generally overlapped high-density hotspots. Large regional and seasonal differences in habitat features of hotspots were found among species but also within species from different regions. Gap analysis (discrepancy between hotspots and IUCN ranges) identified species and regions where more research is required. Main conclusions:This study identified important areas (and habitat types) for Arctic marine mammals using available biotelemetry data. The results herein serve as a benchmark to measure future distributional shifts. Expanded monitoring and telemetry studies are needed on Arctic species to understand the impacts of climate change and concomitant ecosystem changes (synergistic effects of multiple stressors). While efforts should be made to fill knowledge gaps, including regional gaps and more complete sex and age coverage, hotspots identified herein can inform management efforts to mitigate the impacts of human activities and ecological changes, including creation of protected areas.

Zooplankton assemblages along the North American Arctic: Ecological connectivity shaped by ocean circulation and bathymetry from the Chukchi Sea to Labrador Sea

“…So far, knowledge gaps about the geographic distribution of planktivorous long-range seasonal migrators, such as the Bowhead whale (Balaena mysticetus) and various seabird species (Ulrich and Tallman, 2021), complicates the analysis of trophic interactions between vertebrate predators and their zooplankton prey. Still, superimposing our zooplankton and bowhead whale distribution maps (Baird and Bickham, 2021;Hamilton et al, 2022) shows that the areas of high summer density of whales overlap with hotspots of zooplankton biomass in Amundsen Gulf and the south of Lancaster Sound (Figure S3). However, a known area of whale aggregation in the northwestern Hudson Bay does not concur with our mapping of high zooplankton biomass.…”

Postmortem pathology investigation of the wounds from invasive tagging in belugas (Delphinapterus leucas) from Cook Inlet and Bristol Bay, Alaska

“…Hundreds of belugas have been monitored with invasively‐attached satellite tags, providing a wealth of data on movements, habitat use and dive behavior in areas nearly inaccessible to researchers when covered by ice in the dark winter months (e.g. Citta et al, 2017; Hamilton et al, 2022; Vacquié‐Garcia et al, 2018; Yurkowski et al, 2019). Given the inaccessibility of these environments, it is not surprising that very little follow‐up data exists for tagged belugas.…”

Estimating the Spatial Distribution and Future Conservation Requirements of the Spotted Seal in the North Pacific

“…However, when we overlaid the spotted seal range, we discovered that only 5.65-6.22% of the range was protected, meaning that more than 94% of the area was unprotected. Therefore, protected areas (marine reserves, nature reserves and national parks) need to be expanded, and the establishment of protected areas across international borders should be considered to better protect spotted seals and their habitats [59].…”