著者

玉田 一晃

出版者

The Ichthyological Society of Japan

雑誌

魚類学雑誌 (ISSN:00215090)

巻号頁・発行日

vol.52, no.1, pp.17-20, 2005

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Clutch and egg size in the Japanese amphidromous goby, <I>Rhinogobius</I> sp.DA (<I>R. brunneus</I>, dark type), inhabiting small rivers in the southern part of the Kii peninsula were examined. Clutch sizes, ranging between 1043 and 4436, increased with increasing maternal standard length. Spawned egg volume ranged between 0.85 mm<SUP>3</SUP> and 1.38 mm<SUP>3</SUP>, mean egg volumes being similar among the eight rivers sampled during the study. <I>Rhinogobius</I> sp.DA had a relatively larger egg and smaller clutch size compared to those of three other amphidromous <I>Rhinogobius</I> species inhabiting relatively larger rivers in the same region. Inter-specihic egg size variations among the four species appear to result in differing larval survival rates during their migration to the sea.