Climate change effects and the future for Antarctic krill

Climate change effects are already being observed in some regions of the Southern Ocean, where reduced duration and extent of winter sea-ice, ocean warming and ocean acidification threaten the survival of Antarctic krill. This species is critical to the Antarctic ecosystem, where most marine mammal and bird species depend on it as a food source. Whilst there may be some positive effects from the impacts of climate change, their combined effect is likely to be negative and threaten the life cycle and distribution of krill. Long term studies in the southwest Atlantic have linked decreased krill abundance with reduced coverage of winter sea-ice. The Southern Ocean is particularly vulnerable to ocean acidification, which is likely to disrupt the hatching success of krill larvae, and ocean warming may have implications for the range and distribution of krill populations. Recorded catch levels in the krill fishery have also seen recent increases, and fishing pressure coupled with climate change implications may place the future of Antarctic krill in jeopardy. This review will examine current predicted climate change effects and their potential impacts on krill, and whether the combined pressures of increased fishing and a changing environment in the Southern Ocean are effectively managed within the current CCAMLR framework