Heaviside's dolphin
Cephalorhynchus heavisidii
Threat Index

Max Length:
Male: 1.70 m
Female: 1.70 m
Calf: 0.80 - 0.85 m

Max Weight:
Male: 75 kg
Female: 75 kg

Est. Population: Unknown

Diet: Demersal (e.g. – hake) and schooling fish, squid and octopus

IUCN Listing: DD
CMS Appendix: II
CITES Appendix: II
Synonym:
Benguela dolphin, South African dolphin, Heaviside's dolphin

Related Projects:
None

Classification:
Although initially named after Captain Haviside, a case of mistaken identity resulted in this species being named after another Captain, with the surname Heaviside. These distinctive dolphins are one of the smallest and least well known of all cetaceans despite being a coastal species. Few studies have been conducted on Heaviside's dolphins and very little information is available on their biology, life history and population parameters.

Appearance:
Heaviside's dolphin is compact and stocky with a cone-shaped head and blunt beak. The dorsal fin is triangular and pointed, unlike the other members of the genus Cephalorhynchus which have rounded fins. The flippers are small and tapered with blunt tips, and the flukes are notched with pointed tips. The body of the Heaviside's dolphin is grey with a very distinct blackish-blue cape spreading backwards from just in front of the dorsal fin, becoming broader and extending to the tailstock and rear sides. There is a dark patch around each eye which may encompass the face and a bright white patch on the chest and a large white trident-shaped patch on the belly. The arms of the trident project up both sides on the lower rear of the body. There is also a small white patch behind each flipper. The Heaviside's dolphin is easy to distinguish from the other cetaceans in its range due to its smaller size and distinctive colouration.

Behaviour:
Heaviside's dolphins are known to be very active. They will ‘porpoise' at high speed, are avid bowriders and will approach boats from a distance. They have been seen breaching and performing somersaults up to 2m in the air which end with the dolphin slapping its flukes on the surface of the water. They are generally found in groups of two or three but small pods of up to 10 have been documented. Heaviside's dolphins prefer waters less than 100m and are usually seen within sighting distance of the shore. They feed on bottom-dwelling fish, cephalopods, and various crustaceans.

Distribution:
The Heaviside's dolphin is endemic to southwestern Africa. Their range is thought to extend from the Cape of Good Hope in the south to Cape Cross, Namibia in the north. Threats to this species include incidental entanglement in fishing gear as well as some small-scale directed hunting. Due to their restricted range, coastal development, chemical pollution and disturbance by boat traffic are also serious concerns. The IUCN lists this species as Data Deficient.