Feeding habits of bluenose warehou, Hyperoglyphe antarctica (Carmichael, 1819) (Centrolophidae) at seamounts of the Southern Atlantic

Diet of bluenose warehou, Hyperoglyphe antarctica, was investigated from samples collected during commercial fishing (trawling and longlining) on seamounts in the Tristan da Cunha EEZ in the South Atlantic Ocean. Bluenose warehou (57–123 cm TL, N = 309) was found to forage on a broad range of prey, dominated by mesopelagic cephalopods (squid families Onychoteuthidae and Histioteuthidae, Pholidoteuthis massyae and octopus Haliphron atlanticus), Thaliacea (salps and pyrosomes) and a sternoptychid Maurolicus inventionis. Bluenose warehou exhibited a range of foraging strategies from browsing on dense aggregations of passively drifting jelly-like zooplankton to catching mobile nektonic fish. Bluenose also consumed body parts of the gelatinous giant octopus H. atlanticus, which may have been scavenged or predated. The study indicates that bluenose warehou has an unusually broad prey range for a teleost. The diversity of prey and high flexibility of the hunting strategies permitted the bluenose warehou to prosper in the highly changeable and dynamic environments of underwater seamounts.