Reproduction and food habits of two species of sawtail catsharks, Galeus eastmani and G. nipponensis, in Suruga Bay, Japan

Abstract

This study provides information on reproduction and food habits of Galeus eastmani and G. nipponensis in the east and west of Suruga Bay. A total of 731 G. eastmani and 754 G. nipponensis were sampled by commercial bottom trawlers in 1981-1989 and 1992-1996. Size at sexual maturity of both species of Galeus differed between the former and latter period. In G. eastmani, maturity size of females from the east tended to be smaller than those from the west. Both species laid large yolky ova the year round. Both species preyed on a wide variety of marine organisms, mainly Osteichthyes, Cephalopoda and Crustacea. Foods of G. eastmani differed between the east and west by season. Foods in the young stage of G. nipponensis differed from those of immature and mature by season. Body size of the young G. nipponensis was similar for mature G. eastmani, however the young fed on different organisms from G. eastmani in the east. Both species were voracious and opportunistic feeders.