Will krill fare well under Southern Ocean acidification?

Abstract

Antarctic krill embryos and larvae were experimentally exposed to 380 (control), 1000 and 2000 µatm p CO 2 in order to assess the possible impact of ocean acidification on early development of krill. No significant effects were detected on embryonic development or larval behaviour at 1000 µatm p CO 2 ; however, at 2000 µatm p CO 2 development was disrupted before gastrulation in 90 per cent of embryos, and no larvae hatched successfully. Our model projections demonstrated that Southern Ocean sea water p CO 2 could rise up to 1400 µatm in krill's depth range under the IPCC IS92a scenario by the year 2100 (atmospheric p CO 2 788 µatm). These results point out the urgent need for understanding the p CO 2 -response relationship for krill developmental and later stages, in order to predict the possible fate of this key species in the Southern Ocean.