Global warming and the concomitant acidification of oceans is not necessarily a bad thing for all marine invertebrates, according to a study published in a recent issue of the Proceedings of the National Academy of Sciences.
Rebecca Gooding, Christopher Harley and Emily Tang studied the ochre sea star (Pisaster ochraceus), a keystone predator found in the intertidal regions along the coasts of western North America.
The authors reared juvenile sea stars in the laboratory at water temperatures ranging from 5"21C to determine whether growth and feeding rates would increase across the range of water temperatures this species is likely to experience this century throughout much of its geographic range.
They then reared additional juveniles in the presence of various combinations of water temperature and dissolved carbon dioxide to determine the effects of simultaneous and climatically realistic increases in water temperature and carbon dioxide concentration on the growth, feeding, and calcified mass of the sea stars.
The authors found that the sea stars grow faster with increasing temperature and increasing carbon dioxide concentration (although the relative calcified mass of the sea stars decreased with increasing carbon dioxide concentration), without an indication of peaking over the ranges determined in this study.
Although other studies have shown that other species of echinoderms generally suffer from the effects of global warming and ocean acidification, the authors suggest that caution should be exercised when predicting species' responses to climate change on the basis of broad phylogenetic relationships alone.
For more information, see the paper: Gooding, RA, CDG Harley and E Tang (2009) Elevated water temperature and carbon dioxide concentration increase the growth of a keystone echinoderm. Proceedings of the National Academy of Sciences 106, pp. 9316"9321.