A Comparison of Rockfish Species Diversity Inside and Outside MPAs Along a Latitudinal Gradient on the Central California Coast

Sebastes spp. richness is greatest along the latitudes of 33˚-37˚ N, which also corresponds with four of California’s new marine protected areas (MPAs) that were established in 2007 (Ano Nuevo, Point Lobos, Piedras Blancas, and Point Buchon). It is thought that Sebastes spp. richness decreases along a north-south latitudinal gradient and in general that MPAs increase species diversity relative to adjacent non-protected areas. The California Collaborative Fisheries Research Program (CCFRP) has been monitoring MPAs along the central California coast with standardized hook-and-line methods since 2007. An open question remains as to whether Sebastes spp. diversity and total groundfish species diversity follow a latitudinal gradient or if there exists a difference in diversity between protected and non-protected areas. Using 5 years of data (2007-2011), I will be measuring Sebastes spp. and total species diversity using the Shannon-Weiner diversity index (H’), and comparing these analyses between paired MPA and reference sites. Additionally, I will assess whether species diversity declines along the latitudinal gradient.  I hypothesize that species diversity will be constant along the central California coast, but there may be differences in diversity between MPA and reference sites. The results from my analysis can be used by the state of California in its ongoing adaptive management of marine protected areas and in stock assessments of nearshore fish species.