College of Natural Resources & Sciences
In northern California, purple urchin (Strongylocentrotus Purpuratus) populations have exploded, leading to an invasion of the intertidal zone with potential consequences for those communities. We aimed to determine if there was a relationship between surface rugosity and urchin abundance and condition in this recently invaded habitat. We found that urchins took advantage of any intertidal habitat, as abundance was independent of surface rugosity. However, surface rugosity was related to urchin condition, with urchins on rougher surfaces in better condition than those on other surfaces. Rocky intertidal surfaces may therefore provide refugia for overabundant subtidal urchin populations.