Quantifying the Effects of Predator and Prey Body Size on Sea Star Feeding Behaviors.

Body size plays a crucial role in determining the strength of species interactions, population dynamics, and community structure. We measured how changes in body size affect the trophic relationship between the sea star Pisaster ochraceus and its prey, the mussel Mytilus trossulus. We tested the effects of a wide range of predator and prey sizes on sea stars' prey-size preference, feeding rate, and prey tissue consumption.

Elevated water temperature and carbon dioxide concentration increase the growth of a keystone echinoderm.

Anthropogenic climate change poses a serious threat to biodiversity. In marine environments, multiple climate variables, including temperature and CO(2) concentration ([CO(2)]), are changing simultaneously. Although temperature has well-documented ecological effects, and many heavily calcified marine organisms experience reduced growth with increased [CO(2)], little is known about the combined effects of temperature and [CO(2)], particularly on species that are less dependent on calcified shells or skeletons.