(Gray, 1846) - White-beaked dolphin
Distinctive Characteristics
White-beaked dolphins are extremely robust. The beak is short and thick, but set-off from the melon by a crease. The dorsal fin is tall and falcate, with a pointed tip.
The colour pattern is highly variable, but the animals are mostly black to dark grey. The beak and most of the belly are white to light grey, and the beak, especially, is often mottled. An area of light grey with an indistinct border originating on the upper flank broadens to cover most of the tail stock. There is often dark or light flecking in the region between the eye and the flipper.
Each half of each jaw is lined with 22 to 28 sharp teeth.
Can be confused with
White-beaked dolphins are most likely to be confused with Atlantic white-sided dolphins, from which they can be distinguished by differences in coloration and beak length. In the few areas where they overlap with bottlenose dolphins, care must be taken to distinguish between these 2; colour-pattern differences are most useful.
Size
Adults are up to 3.2 m in length (males grow larger than females). Newborns are between 1.2 and 1.6 m.
Geographical Distribution
White-beaked dolphins inhabit cold temperate to subpolar oceanic waters of the North Atlantic, from Cape Cod and Portugal, north to central Davis Strait, central Greenland, Iceland, and northern Norway. There are also records from the western Mediterranean.
Biology and Behaviour
Groups of less than 50 are most common, but herds of many hundreds have been seen. These animals are active, often leaping and breaching. While feeding they sometimes associate with large whales.
There appears to be a calving peak in summer and early autumn, but not much is known about reproduction in this species.
White-beaked dolphins feed on a variety of small schooling fishes, squid, and crustaceans.
Exploitation
There is a long history of hunting for white-beaked dolphins in Norway, the Faeroe Islands, Greenland, and Labrador. Hunting in some areas continues today. Incidental catches in fishing gear occur, but are not thought to be high enough to represent a threat to this species.
IUCN Status
Insufficiently known.