Four-toothed whales or giant beaked whales are beaked whales in the genus Berardius. They include Arnoux's beaked whale (Berardius arnuxii ) in cold Southern Hemisphere waters, and Baird's beaked whale (Berardius bairdii ) in the cold temperate...
Arnoux's beaked whale (Berardius arnuxii) is one of the species of beaked whales found in great tracts of the Southern Ocean. Little is known about their behavior due to their secretive nature and infrequent encounters with live individuals.