Data are for an experiment evaluating the effects of algal diet on consumption, growth, and gonad weight of an important kelp forest grazer, the purple sea urchin, Strongylocentrotus pupuratus over a 13 week period (November 2010 - February 2011). Four co-occurring species of macroalgae known to be part of its diet were offered: two kelps Macrocystis pyrifera and Pterygophora californica, and the red algae Chondracanthus corymbiferus and Rhodymenia californica. During 9 consectutive trials in a controlled laboratory setting, we measured consumption, test (exoskeleton) growth, jaw growth, change in whole body wet weight and gonad weight of urchins fed one of five experimental diets. The algae chosen represent a large proportion (> 75%) of the algal biomass in Santa Barbara Channel reefs (California, USA). Changes in the availability of these four species of macroalgae could have large implications for the performance of purple sea urchins and consequently, for the structure of subtidal reef communities.
These data are presented in a paper describing the effects of five southern California macroalgal diets on the consumption, growth and gonad weight of the purple sea urchin: Matthew C. Foster, M., Byrnes, J. E. K., D. C. Reed. 2015. Effects of five southern California macroalgal diets on consumption, growth and gonad weight in the purple sea urchin, Strongylocentrotus purpuratus. PeerJ. DOI: 10.7717/peerj.719