This species generally occurs in deep, cold temperate and subpolar waters, especially in areas with steep-bottomed slopes beyond the continental shelf edge (Kasuya 2002). However, some sightings have been associated with shallower regions, coastal waters, continental slopes or seamounts (Jefferson et al. 1993). Hobson and Martin (1996) observed groups of Arnoux’s beaked whales near the Antarctic Peninsula and found that their breath-holding capabilities make this species one of the most accomplished mammalian divers, capable of swimming up to an estimated 7 km between breathing sites in sea ice. The species seems well-adapted to life in ice-covered waters and may be able to exploit food resources inaccessible to other predators in the region (Ponganis et al. 1995).

Little is known of the feeding habits of Arnoux's beaked whales but they are assumed to be similar to those of their Northern Hemisphere relatives, Baird's beaked whales, consisting of benthic and pelagic fishes and cephalopods (Jefferson et al. 1993, Culik 2004). Squids are probably the main dietary items.