山陰沿岸における稚仔魚の沖合および岸寄り分布

抄録

Offshore and nearshore distributional patterns of fish larvae were studied on materials obtained 5 to 105 miles off the San-in Coast, the Sea of Japan.The materials consisted of 514 samples containing 3, 528 individuals collected in 1978-1979.The patterns of vertical distribution of major species were classified into three types: (1) subsurface layer: Engraulis japonica, Cololabis saira, Sebastes spp., Stephanolepis cirrhifer; (2) middle layer: Sebastes pachycephalus (?), Etrumeus micropus, Trachurus japonicus, Scomber japonicus, Callionymidae spp., Glyptocephalus stelleri, Hippoglossoides dubius, Paralichthys olivaceus; (3) deeper layer: Glossanodon semifasciatus, Cepola schlegeri (?), Liparidae spp., Triglidae spp., Brotulidae spp., Maurolicus muelleri.
The patterns of horizontal distribution were classified as follows: (1) nearshore as-semblage: S.cirrhifer, Triglidae spp., Sebastes spp., S.pachycephalus (?), Liparidae spp.; (2) middle area assemblage: C.schlegeri (?), T.japonicus, G.semifasciatus, Brotulidae spp., G.stelleri, H.dubius, P.olivaceus; (3) nearshore assemblage extending to offshore distri-bution;S.japonicus, Callionymidae spp., E.micropus; (4) offshore assemblage: C.saira, M.muelleri, E.japonica.
The distributional pattern of larvae was also considered using a combination of vertical and horizontal distributions.The most outstanding pattern was middle layer-middle area assemblage in 18 principal species.
The relationship between the mode of reproduction and distributional pattern of larvae was discussed.Although clear relationship was not found between the two, it was noted that some of the species belonging to the nearshore assemblage produced non-pelagic eggs or were ovoviviparous.Some considerations of the relationship between larval distribution and adult habitat were given.