Feeding Behavior, Prey Consumption, and Growth of Juvenile Red Hake

Abstract

Abstract Juvenile red hake Urophycis chuss were collected while they were inhabiting sea scallops Placopecten magellanicus, and the effects of appetite and food availability on prey consumption and growth were examined under laboratory conditions. Fish took increasing amounts of live amphipods Gammarus annulatus with increasing periods of food deprivation up to 40–50 hours. The largest portion of a meal was consumed within the first 3 minutes following prey introduction. With longer periods of food deprivation, red hake increased the time their chemosensitive pelvic fins were extended, indicative of a rise in feeding motivation. The average amount of sand shrimp Crangon septemspinosa consumed by fish was 7.4% of body weight/day. Under conditions of high prey abundance, fish grew at rates equal to field growth rates, but under conditions of low prey abundance, growth rate was inhibited. Prey availability can influence the growth rate, which might lead to size differentials within a cohort. Received Novembe...