Settlement Characteristics and Habitats Use of Lake Biwa Catfish Silurus biwaensis Measured by Ultrasonic Telemetry

Abstract

The trackings of Lake Biwa catfish were executed to examine how migratory they were and what habitat they selected in Lake Biwa in 1993, 1995 and 1996 by ultrasonic biotelemetry. Eight individuals were tracked for a maximum of 118 days in the South Basin, and 11 individuals for a maximum of 319 days in the North Basin. In the South Basin experiments, 7 individuals quickly returned to their caught place, and 5 individuals didn't change their settled positions in the South Basin from July to October. In the Shiozuwann Bay experiments, 9 individuals settled around the shallow floor near their spawning ground in the Shiozuwann Bay throughout the year. It was shown that Lake Biwa catfish had settlement characteristics, less migratory, and mainly inhabited in the shallow area near the spawning ground all the year round.