Pelagic habitat use of an adult Japanese male loggerhead turtle Caretta caretta examined by the Argos satellite system

Abstract

Adult female sea turtles land on sandy beaches to nest, but males usually never come ashore throughout their life with the exception of some male green turtles Chelonia mydas that crawl ashore to bask. 4] There is very little information on the migratory behavior of male loggerheads. Sakamoto et al. tracked an adult male loggerhead that had been incidentally captured in a set-net in Kushimoto, Wakayama Prefecture, Japan, during a non-reproductive season (January) in 1996. After release, the turtle migrated to the south-east along the Kuroshio Current and stayed at the south of the Current in the pelagic Pacific throughout the winter. This finding suggests that some male log-gerheads inhabiting the coastal waters of Japan utilize this area as their feeding and wintering ground. In November 1998, an adult male loggerhead turtle was captured again by another set-net in Kushimoto. Following the method described by Sakamoto et al., 7 a satellite transmitter was attached to this turtle. In the present paper, we report the findings of this tracking study.