Little is known about the food habits of Berardius arnuxii and most information comes from comparison with B. bairdii. Berardius bairdii is primarily teuthophagous and piscivorous (squid- and fish-eating), but other benthic, epibenthic, and pelagic prey are also eaten. Berardius arnuxii is presumed to have a similar diet with slight variation due to the difference in geographic range. Their association with pack ice suggests that B. arnuxii may be exploiting a unique niche that is not available to most other cetaceans who do not have access to prey found under ice.

Animal Foods: fish; mollusks

Primary Diet: carnivore (Piscivore , Molluscivore )