- Long-term effects of climate change on non-indigenous species are rarely studied
- Pacific oysters were exposed to warming, ocean acidification and reduced salinity
- Warming and ocean acidification predicted for the year 2100 did not affect fitness
- Low salinity reduced clearance rates and increased oxygen consumption rates
- Long-term observations highlighted potential seasonal trends in physiological rates
The current global redistribution of biota is often attributed to two main drivers: contemporary climate change (CCC) and non-indigenous species (NIS). Despite evidence of synergetic effects, however, studies assessing long-term effects of CCC conditions on NIS fitness remain rare. We examined the interactive effects of warming, ocean acidification and reduced salinity on the globally distributed marine NIS Magallana gigas(Pacific oyster) over a ten-month period. Growth, clearance and oxygen consumption rates were measured monthly to assess individual fitness. Lower salinity had a significant, permanent effect on M. gigas, reducing and increasing clearance and oxygen consumption rates, respectively. Neither predicted increases in seawater temperature nor reduced pH had a long-term physiological effect, indicating conditions predicted for 2100 will not affect adult physiology and survival. These results suggest that M. gigas will remain a globally successful NIS and predicted CCC will continue to facilitate their competitive dominance in the near future.
Pack K. E., Rius M. & Mieszkowska N., in press. Long-term environmental tolerance of the non-indigenous Pacific oyster to expected contemporary climate change conditions. Marine Environmental Research. Article (subscription required).