Islands in the ice: Climate change and ecological connectivity among Antarctica’s ice-free areas

Jasmine Lee (1), Richard Fuller (2), Iadine Chades (3), Justine Shaw (4), Ben Raymond (5), Aleks Terauds (6)

 

1 University of Queensland, St Lucia, QLD, 4072, jasmine.lee1@uqconnect.edu.au

2 University of Queensland, St Lucia, QLD, 4072,  r.fuller@uq.edu.au, RichFullerUQ

3 CSIRO, GPO Box 2583, Brisbane, QLD, 4001,  iadine.chades@csiro.au, iadinec

4 University of Queensland, St Lucia, QLD, 4072,  j.shaw6@uq.edu.au, justine_d_shaw

5 Australian Antarctic Division, Channel Highway, Kingston, TAS, 7050, ben.raymond@aad.gov.au

6 Australian Antarctic Division, Channel Highway, Kingston, TAS, 7050, aleks.terauds@aad.gov.au

Though making up only 0.32% of the continent, permanently ice-free areas in the Antarctic are home to over 99% of its biodiversity, including arthropods, nematodes, lichens, fungi and tardigrades. In addition, many vertebrates including pinnipeds and penguins rely on ice-free areas at certain times of the year for breeding. Despite intensive research on climate change impacts around the world, almost nothing is known about how ice-free areas might be affected, which is critical to understanding species movements. Unlike most of the world, where climate change is set to fragment species distributions, in Antarctica we might expect ice-free areas to increase in size and become more connected. Consequently dispersal and gene-flow among regions that have maintained genetic and evolutionary distinctiveness for up to 60 million years could lead to rapid biotic homogenization, extinctions, and the further spread of invasive species, which are already posing a substantial threat to Antarctic biodiversity in some regions. Here we present a framework for understanding climate change impacts on Antarctic ice-free areas. Using newly-available regionally specific climate predictions, we show how the distribution and connectivity of Antarctic ice-free areas might change under IPCC5 climate change scenarios, and explore the ecological implications of these changes for Antarctic terrestrial biodiversity. We demonstrate potentially large increases in total ice-free area extent and disrupted patterns of connectivity among those patches. This work represents an essential first step for predicting the movements of both native and invasive species under climate change and for informing conservation planning and management in the region.