Settling Mechanism of Larvae of Bastard Halibut, Paralichthys olivaceus, in the Nursery Ground, Estimated from the Size Distribution

Abstract

This study was carried out to estimate the dates of settlement of larvae of the bastard halibut and to guess the mechanism how they settles on the bottom of their nursery ground in the Genkai-Nada, the Japan Sea.
Four size-groups of the bastard halibut were recognized during the growing period (May to September) after their settlement, based on the shift of modes of the length in their growth curves. The dates of their settlement were estimated to be 9th and 24th of April and 7th and 22nd of May by appling B_ERTALANFFY'S growth equation to the present data. These four dates of their settlement were endorsed by field surveys of settled youngs of the bastard halibut, and almost coincide with the four spring tides during the period.