Age and growth of oonibe fish Argyrosomus japonicus off Miyazaki Prefecture

Abstract

　Age and growth of oonibe fish Argyrosomus japonicus, the fishery catch of which has increased in recent years off Miyazaki Prefecture, were examined by the otolith sectioning method. The spawning season peaked in February, and an opaque zone was formed from February to May. Opaque zone counts were the same as the actual age for released and recaptured individuals (n=142). Fish sampled from the fishery catch were 99-1110 mm in total length, and aged 0+ to 10+. The growth trajectory shows a rapid linear increase till 800 mm and 3+ and stagnant increment around 900-1100 mm after 5+ years old. VBGF was calculated as TLt=1089{1−exp[−0.364×(t+0.142)]}. Maturation length and age were estimated to be 800 mm and 4 years old, respectively.