Acoustic survey of distribution and abundance of micronectonic fish, Maurolicus muelleri, in the southwestern Japan Sea

Seasonal distribution and abundance of micronektonic fish, Maurolicus muelleri, in the southwestern Japan Sea were investigated in relation to oceanographic conditions by means of the acoustic method. In the northern area of 130 nautical miles off Hamada/Hinomisaki coast, no clear seasonal fluctuations of geographical center of distribution and southern limit were found. However, increase of fish abundance occurred in spring, and decrease in autumn. Correlations were exist between water temperature latitude of 10 degree C at a depth of 100 m and that of the center of fish distribution; the center of fish abundant area moves southward/northward with cold water. It is suggested that "wall effect" for the formation of common squid and mackerel fishing ground is affected by the distribution of the food fish.