Vulnerability of Southern Ocean biota to climate change

Most Southern Ocean life is specifically adapted to the unique Antarctic environment. This extensive region is characterized by low temperature, a glaciated coastline and distinct seasonality in sea-ice cover, light regime and biological productivity. Here, we examine the vulnerability of Southern Ocean biota to recent changes to inform society and stakeholders about primary areas of concern and the most pressing fields for future study. Most species inhabiting the Southern Ocean are assumed to be sensitive to climate change. Growth of microalgae, the base of the food web, depends critically on sea-ice cover. Predicted sea-ice reduction will have cascading effects on higher trophic levels. Organisms living in the ice, krill, fish, penguins, seals, and whales will need to find new habitats or feeding grounds. However, thresholds of climatic conditions for population or community collapse are largely unknown. Some organisms might even benefit from climate change through increased reproduction and growth rates