紀伊水道外域産マダイの年齢と生長

抄録

Based on the scale reading, the relationship between age and growth of the red sea bream Pagrus major in the waters of the southern part of Wakayama Prefecture was studied. The ringmarks on scales are generally obscure in comparison with those in the Inland Seas, and it was almost imposible to read scales from about 7.5% of the whole. The periods of ring formation and spawning are from about March to April. The growth laws in length (L, mm) and weight (W, g) are estimated as follows:
L_t=670[1-exp{-0.211(t+0.079)}], W=0.00001994L³
While, anabolism and catabolism have been calculated from growth parameters given above. The biggest value of the daily growth of weight is 1.53g. at the age of 5. This growth is pretty bigger than that described in former studies which have treated the same species in other Japanese coastal waters. This fish hibernates in watcr of 12°C and below, Therefore, it is reasonable that the geographical variations of the growth and ring formation come from the temperature difference and reflects the metabolism difference of the fish in each water.