Impacts of climate change on cetacean distribution, habitat and migration

Climatic changes have had significant impacts on marine ecosystems, including apex predators such as cetaceans. A more complete understanding of the potential impacts of climate change on cetaceans is necessary to ensure their conservation. Here we present a review of the literature on the impacts of climate change on cetacean distribution, habitat and migrations and highlight research gaps. Our results indicate that due to rising sea surface temperatures (SSTs) and/or reducing sea ice extent, a variety of impacts on the distribution, habitat and migration of cetaceans have been observed to date and several more are predicted to occur over the next century. Many species have demonstrated a poleward shift, following their preferred SSTs to higher latitudes, and some have altered the timing of their migrations, while others appear not to be affected. These changes may benefit certain species, while others will be placed under extreme pressure and may face increased risk of extinction. Broader implications may include increased inter-specific competition, genetic alterations, ecosystem-level changes and conservation challenges. Existing research on the topic is both extremely limited and unevenly distributed (geographically and phylogenetically). Further research is necessary to determine which species and populations are most vulnerable and require the earliest conservation action.