Age, Growth, and Maturity of Cabezon, Scorpaenichthys marmoratus in California
Joanna Grebel email: jgrebel@mlml.calstate.edu

The cabezon, Scorpaenichthys marmoratus, is a major component of the live fish fishery along the western United States with landings averaging 240,000lb since 1995. Though size and catch regulations for both commercial and recreational fishing exist, they are based on little scientific information and important life history information is limited in this species. This research will provide the first validated age estimates and maturity information of cabezon in California. Ages were estimated from sectioned otoliths and will be validated by edge analysis. Sectioned dorsal spines, dorsal fin rays, and vertebrae will be examined for potential use as alternative ageing structures. von Bertalanffy growth parameters indicate that females grow slower and reach a larger size (L8= 693.02, k= 0.15, t0= -1.57 (n=167)) than males (L8= 505.06, k= 0.21, t0=-2.46 (n=93)). Both sexes reached a maximum age of 13 years in this study. Males reach sexual maturity at a smaller size (10%=160 mm, 50%=271 mm, 90%=355 mm) than females (10%=175 mm, 50%=301 mm, 90%=400mm). Ongoing research will involve more rigorous validation using mark-recapture with OTC.