Baseline monitoring and characterization of rocky intertidal fish communities in Northern California

A network of new Marine Protected Areas (MPAs) has been established in northern California, covering 137 square miles of coastline, with the goal of maintaining commercially and recreationally important species and to preserve biodiversity. This is the first study in California to create a biodiversity and phylogenetic baseline of rocky intertidal fish communities within MPAs and nearby reference sites. Diversity, abundance, and size structure of intertidal fishes were compared among seven sites from Fort Bragg to Crescent City, CA during the summers and winters of 2014 and 2015. A total of 34 species were collected throughout sampling, just three less than the estimated 37 species based on rarefaction analyses, with the highest diversity and abundance observed at unprotected sites. Many young-of-year recruits of recreationally and commercially important species were collected, indicating the rocky intertidal zone may be an important nursery area for some species. In contrast to previous studies in this region, very few rockfish (Sebastes) recruits were found in intertidal areas. Pools had a very high probability of containing fish, but, with the exception of the sculpin Oligocottus snyderi, even the most abundant species were detected in less than half of the pools surveyed. While 28 surveys were conducted, an estimated 34 more would have been necessary to detect all species present in the intertidal zone of this region. A phylogenetic analysis was conducted on DNA Barcode data using the mitochondrial cytochrome c oxidase I gene (COI) of intertidal fish including multiple individuals of the same species from different regions along the Eastern Pacific coast. All species were resolved as monophyletic, indicating great potential for use of the COI gene in species identification