The role of zooplankton in the diets of certain sub-Antarctic marine fish.

Abstract

Nototheniids and channichthyids were studied at Kerguelen and Crozet islands. Young of Notothenia rossii are coastal and feed on benthic invertebrates but adults, which live offshore at depths of 100-400 m, have diets mainly composed of planktonic organisms such as euphausiids, medusae and salps. Notothenia squamifrons is widely distributed in the area, but rarely occurs in shallow waters. It feeds on salps, medusae and amphipods. Dissostichus eleginoides is a predator on other fish, its young feeding on euphausiids and other zooplankters. The diet of Champsocephalus gunnari is based on euphausiids, pelagic amphipods and pelagic fish, such as myctophids. Channichthys rhinoceratus is mainly a predator of young fish. These plankton-based diets suggest that the fishes' foraging behaviour is attuned to the movements of their prey. -from Authors