Dolphins Beaked whales are the least known of all whales and dolphins. There are currently 20 known living species, of which 8 have been recorded in South Australian waters, but there could be more that have yet to be discovered. Beaked whales have prominent jaws and through their evolution have lost all teeth in the upper jaw and most teeth in the lower jaw. All but two male beaked whale species have only two or four teeth located in the lower jaw. These teeth have become greatly enlarged and in some species have actually developed as tusks.
Females appear to have no visible teeth.
The diet of beaked whales consists of fish and squid. They are medium sized whales and inhabit the deep, open ocean. They appear to be very deep divers, perhaps even equalling the Sperm whale. Because most species are rare, there is very little known about their biology or population size. Most are only known from strandings and a very few confirmed sightings at sea.