| Summary: | The Southern Ocean and Western Antarctic Peninsula (WAP) are an ecologically vital polar marine habitat supporting rich stocks of plankton, krill, and top predators. Abiotic factors such as sea ice dynamics, sea surface temperature, and bathymetry are key predictors of the spatial distribution of plankton blooms and therefore greatly affect krill and baleen whale populations. This study aims to understand the habitat preference of Antarctic minke whales (Balaenoptera bonaerensis) with respect to sea ice dynamics and other abiotic factors around the WAP. Ship- and aerial-based surveys have suggested this mesopredator exhibits a pagophilic nature, and we provide the first satellite tag-based habitat analysis that confirms this hypothesis. As a relatively small baleen whale species, the Antarctic minke whale is well suited to life in the pack ice where larger cetacean species are unable to maneuver or hunt as successfully. Daily movements were recorded with ARGOS satellite tags and behavioral states were described using the Multi-Scale Straightness Index. Generalized additive models (GAMs) elucidated ecological relationships between the whales and the environment. The GAMs demonstrated a strong preference for sea ice habitat, where the minke whales preferred to forage close to the sea ice edge as well as within the dense pack ice. The GAMs also indicated individual preferences with respect to sea surface temperature and bathymetry, demonstrating the importance of these variables in locating dense prey aggregations. The coupled relationship between minke whales, krill, and sea ice suggests that these whales will be sensitive to changes in sea ice concentration, extent, and duration, making them particularly vulnerable to climate change. Results from this analysis will therefore be beneficial for conservation and future research. DeLiberty, Tracy L. Oliver, Matthew J. M.S. University of Delaware, Department of Geography
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