Age and growth of crimson sea bream Evynnis tumifrons off the southwestern coast of Kyushu, Japan

Abstract

Age and growth of crimson sea bream Evynnis tumifrons were studied using samples collected from October 1999 to August 2013 off the southwestern coast of Kyushu, Japan. Ring marks (outer edges of opaque zones) on the 1805 transversely sectioned otoliths were counted and seasonality in their deposition was validated by marginal increment. Our results revealed that one ring mark was formed per year from late spring to early summer. Assuming December as the birth month, ages were assigned to every individual according to the number of ring marks and the value of marginal increments. Growth was estimated by fitting the von Bertalanffy growth function to the length-at-age and weight-at-age data. The estimated growth curves did not differ significantly between the sexes, and the growth curve of the pooled data was $$L_{\text{t}} = 271\left( {1 - { \exp }\left( { - 0.604\left( {t + 0.193} \right)} \right)} \right)$$ for length-at-age and $$W_{\text{t}} = 519\left( {1 - { \exp }\left( { - 0.484\left( {t + 0.625} \right)} \right)} \right)^{3}$$ for weight-at-age. The maximum age observed was 15 years for females and 16 years for males.