Life History Aspects of Greenspotted Rockfish (Sebastes chlorostictus) from Central California

摘要

A consolidated life history of greenspotted rockfish, Sebastes chlorostictus, is compiled from past studies and recent data from the Southwest Fisheries Science Center's Groundfish Ecology Cruise program in central California. Our data indicate similar growth rates for males and females; the von Bertalanffy parameters for both sexes combined are Linfinity sign = 457 mm fork length (FL), k = 0.062 yr (to the minus 1 power)and t (sub 0) = -1.16 yr. The estimated length-weight relationship is W = 0.00001032L(sup 3.108) (weight in grams), and the estimated annual natural mortality rate (M) is roughly between 0.04 and 0.07 yr(to the minus 1 power). Length at 50% maturity is 262 mm FL, and fecundity ranges from 14,000 to 414,000 eggs. Linear models provide the best fit of absolute fecundity data with length and weight. In central California, females spawn from March to August, peaking from April to June. The observed life history characteristics of S. chlorostictus (slow growth, sedentary adults, extreme longevity, and late maturity), combined with declines in mean length, may indicate that this species is vulnerable to overexploitation.