The biology of Acanthoclinus quadridactylus (Bloch and Schneider) (Teleostei-Blennioidea). I. Age, growth, and food

Abstract

Age, growth, and food of a population of Acanthoclinus quadridactylus were studied from December 1959 to December 1960. Age and growth were investigated by means of length frequencies of fish and by the analysis of growth zones shown in their sagittal otoliths. The growth rate decreases with age and growth is retarded during winter months. Fish live to a maximum age of at least nine years at which time they are approximately 20 cm long. There are no marked differences in growth or longevity between the sexes.

Analysis of gut contents showed that A. quadridactylus is an omnivorous carnivore. Diet is apparently restricted by availability rather than by selective feeding. Decapods were the most important food organisms and Petrolisthes elongatus was the most important single species. Other food organisms included (in order of importance) isopods, barnacles, amphipods, chitons, gastropods, bivalves, polychaetes, fish, and bryozoans. There is evidence of a change of diet in the first year of life.