Effects of Ocean Acidification on Calcification of the Sub-Antarctic Pteropod Limacina retroversa

Ocean acidification is expected to impact the high latitude oceans first, as CO 2 dissolves more easily in colder waters. At current rate of anthropogenic emissions, sub-Antarctic Zone will start experience undersaturated conditions with respect aragonite within next few decades, which affect marine calcifying organisms. Shelled pteropods, a group zooplankton, are considered be especially sensitive changes carbonate chemistry because their thin shells. Limacina retroversa most abundant pteropod waters, and plays an important role pump. However, not much known about its response ocean acidification. In this study, we investigated differences calcification between L. individuals exposed past (pH 8.19; mid-1880s), present 8.06), near-future 7.93; predicted for 2050) sub-Antarctic. After 3 days exposure, responses were quantified by calcein staining, shell weighing, Micro-CT scanning. pteropods conditions, occurred over entire leading edge last whorl, whilst incubated under mostly invested extending shells, rather than shell. Moreover, formed larger volumes compared future suggesting that already decreased today’s Shells did increase weight during incubation, had lower density further compromised future. This demonstrates sensitivity relatively small short-term chemistry. A reduction rapidly acidifying waters have major on aragonite-CaCO export from oceanic surface deep sea.