Bull. Jpn. Soc. Fish. Oceanogr. 71(4), Page 263-269, 2007
  Growth in larval and juvenile Japanese sand lance Ammodytes personatus in eastern Seto Inland Sea determined by daily growth increments in otoliths

Takayuki Kusakabe1†, Hiroaki Omi1, and Mami Saito2

1Marine Fisheries Research Center, Research Institute of Environment, Agriculture and Fisheries, Osaka Prefectural Government, Misaki, Sennan, Osaka 599-0311, Japan
JAPAN NUS Co., Ltd., Yokohama Kanazawa High-technology Center 5F, Fukuura 1-1, Kanazawa-ku, Yokohama 236-0004, Japan
kusakabet@o-suishi.zaqrs.jp

In order to improve the accuracy of growth rates prediction in larval and juvenile Japanese sand lance Ammodytes personatus, growth analysis in body length using otolith microstructure was carried out. Because the widths of the rings near the center of otoliths are very narrow, we used a scanning electron microscope together with a biological microscope. In laboratory reared larvae, growth trajectories of body length back-calculated by the biological intercept method corresponded with those measured directly by periodical sampling. This result supports that application of this method to the growth trajectories of natural A. personatus is adequate. Upon application of the method to the fish caught by commercial boat seine fishery on the opening days of fishing seasons in 1997, 2000, 2001, and 2004, the growth in early life history of the A. personatus showed logistic-like trajectories. There was a strong correlation between growth rate at the 37th day after hatching (0.64-0.88 mm day-1) and mid-layer water temperature in Osaka Bay during early-February. Hatching dates estimated by counting otolith daily growth increments agreed with those estimated by field investigations on mature adult fish in each year.

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