STUDIES ON THE OCCURRENCE OF EGGS AND LARVAE OF FISHES IN ADJACENT WATERS TO OKI ISLANDS : II. THE SEASONAL ABUNDANCE

Abstract

In winter only about five species of fish larvae were collected and in summer they increased to about 30 species. Larvae of fishes were most abundantly collected during June to August and the eggs were abundant in the period of April to July. In winter both were scanty. The variations of total catch were subject to increment or decrement of the eggs or larvae of Sardinops melanosticta (T. et S.), Engraulis japonica (HOUTTUYN), Cololabis saira (BREVOORT) and Upeneus bensasi (T. et S.). Comparing with those in the adjacent waters of the Goto Islands, the period of occurrence in this area was shorter and later in most species, and several species were common in the Oki area but scarce in the Goto area. The dominant species were Sardinops melanosticta and Etrumeus micropus (T. et S.) in Spring, Engraulis japonica and Upeneus bensasi in summer, and Goniistius zonatus (C. et V.) (or G. quadricornis (GUNTHER)) and Labracoglossa argentiventris PETER in autumn.