Rocky Intertidal Macroinvertebrates of the Southern California Bight: An Overview and Checklist

A total of 349 epibenthic taxa of macroinvertebrates were recorded from 7 mainland and 15 island rocky intertidal sites in the Southern California Bight. The occurrence of these taxa among the 22 sites is presented as a checklist organized by phyla and classes. The majority of these were mollusks (188), followed by sponges (42) and crustaceans (30). Highest numbers of taxa were recorded from: Coal Oil Point (125); Big Fisherman's Cove, Santa Catalina Island (124); Santa Rosa Island (122); Willows Anchorage, Santa Cruz Island (122) and Government Point (120). Sites having the highest numbers of common taxa (i.e., those whose average densities exceeded one individual per m2) were located on islands, and included: Willows Anchorage, Santa Cruz Island (3 8 taxa); Catalina Harbor, Santa Catalina Island (36); Prisoners Harbor, Santa Cruz Island (34); Frenchy's Cove, Anacapa Island (33); Cave Canyon, Santa Barbara Island (33) and Big Fisherman's Cove, Santa Catalina Island (33). The most abundant taxa (based on density and averaged over all sites) were Chthamalus fissus / C. dalli, followed by Littorina keenae, Phragmatopoma californica and Tetraclita rubescens. Based on percent cover, the most abundant taxa were C. fissus/C. dalli, P. californica, Mytilus californianus and Anthopleura elegantissima. With the exception of sponges, the number of northerly and southerly range extensions along the Pacific Coast recorded by this study were few.