Age and Growth of Korean Flounder Glyptocephalus stelleri in Funka Bay, Hokkaido

Abstract

For maintaining and increasing in natural stock of Korean flounder Glyptocephalus stelleri their ages and growth in Funka Bay, Hokkaido were studied on the basis of samples caught by an otter trawl net and commercial gill nets. Observation of the otolith margin verified that annuli, outer margins of the opaque zone, were mainly produced between August and September during the birth period. Growth in both sexes was expressed by the von Bertalanffy asymptotic growth functions as SL_t = 393.1 [1-exp {-0.145 (t+0.081)}] for females and SL_t = 393.1 [1-exp {-0.134 (t+0.088)}] for males, where SL_t is standard length in mm and t is age in years. The growth rates of 1 year old and later in Funka Bay are higher than those in Japan Sea off San-in with this disparity considered to be related to food availability.