水温が伊勢湾産イカナゴ初期生活史の成長と加入資源量に与える影響

抄録

Growth of Japanese sandeel Ammodytes personatus (23.7–38.4 mm body length) collected in Ise Bay, central Japan, was investigated. The growth trajectories of individual larvae were back-calculated by using the biological intercept method based on the allometric relationship between otolith radius and body length. Because the inner rings are obscurely visible when examined under a biological microscope, we used a scanning electron microscope to identify them. The number of inner rings is higher in years of low temperature (Av. 18.5°C) than in years of high temperature (Av. 16.6°C). To align temperature to a logistic growth curve, we assumed the linear relationship between growth rate and temperature while keeping the L_max constant. By doing so, the logistic growth curve provides a more accurate estimation. From the field data, it was analyzed that high temperature resulted in a high growth rate and a low recruit number.