These data are the annual mean abundances of three age-classes of black surfperch and their prey at each of 11 sites at Santa Cruz Island, California. Reported values are a) the average number of adult black surfperch, young-of-year black surfperch, and one year-old black surfperch per 40m x 2m transect (for all transects), and b) total food availability (grams per 0.1 m squared) at each site. Food availability includes biomass of caprellid and gammarid amphipods and is calculated from the mean density within Gelidium spp. (for caprellids) and all other foliose or turfing algae (for gammarids). The data also include one year lags for each variable, i.e. the value of the variable at that site in the previous year.