Kyoto Institute of Oceanic and Fishery Science, Miyazu, Kyoto 626-0052, Japan
Age and growth of willowy flounder Tanakius kitaharai were estimated from sagittal otoliths of 1776 specimens collected from western Wakasa Bay, Japan. Examination of the outer margin of the otolith showed that opaque and hyaline zones composed the ring mark, which was formed once a year. The von Bertalanffy's growth equations for body length (Lt) at full age (t) were as follows: Lt=206.8(1−exp(−0.335(t+0.129))) for males; Lt=238.5(1−exp(−0.297(t+0.157))) for females. The growth of females greater than that of males. Maturity rate for each age class was also estimated. Based on the age-length key, age compositions were investigated for willowy flounder caught by commercial Danish seine with two different mesh openings of cod-end.