Hector’s Dolphin is also known as the White-headed Dolphin (Cephalorhynchus hectori). The Hector’s dolphin is the most well-known of the four dolphins in the genus Cephalorhynchus.
Hector’s Dolphin has a sub species called ‘Maui’s Dolphin’ (Cephalorhynchus hectori maui) which is found off the northwest coast of New Zealand’s North Island, both dolphins are endemic to this island.
The Maui Dolphin is the most endangered subspecies of all marine mammals.There are said to be only about 100 Maui Dolphins in the wild. The Maui Dolphin is critically endangered due to being caught in fishing nets and being wounded by boat propellors.
The Hector’s dolphin was named after Sir James Hector. Sir James was the curator of the Colonial Museum in Wellington (now the museum of New Zealand – Te Papa). He examined the first specimen found of the dolphin. Sir James lived from 1834 to 1907. He was the most influential New Zealand scientist of his time.
Hector’s Dolphin Characteristics
The Hector’s dolphin does not have a bottle-shaped snout. The forehead of the Hector’s dolphin slopes down to the tip, so it does not create a protruding beak like the bottlenose dolphin. It has a small, rounded dorsal fin, all other New Zealand dolphins have crescent shaped fins.
Their fluke has pointed tips and concave trailing edges. The overall colour of this dolphin is a pale grey. Their forehead is grey with streaks of black. The tip of the beak is black. The throat and chest are white. There are dark grey patches running from the flippers to the eyes. The belly is also white with a stripe running up the sides from under the dorsal fin. The bulk of the back and sides is the same lighter grey of the beak. The tail stock is narrow.
At birth, the Hector’s dolphin weighs about 9 kilograms and grows to about 40 to 60 kilograms at adulthood. At about 1.4 metres in length, it is one of the smallest cetaceans. The Hector’s dolphins have a life span of about 20 years.
Hector’s Dolphin Behaviour
Hector’s dolphins like to have company. They usually swim in groups of between 2 and 12 dolphins. Hector’s dolphins are active animals, readily bow-riding and playing with seaweed. When leaping from the sea, individuals will often land on their side, creating a loud splash (their vertical and horizontal dives are much less noisy).
Hector’s dolphins tend to stay in the same area – sometimes for life. Here, they spend their days swimming along the coastline, surfacing to breathe, diving to find food and playing.
Hector’s Dolphin Diet
Hector’s dolphins feed on fish and other sea creatures found in shallow water with a sandy bottom, such as flounder, red cod, mackerel, crabs and squid.
Hector’s Dolphin Communication
Hector’s dolphins use echo-location to locate their prey. Dolphins send out a stream of high frequency clicking noises and when the sound strikes an object it bounces back and the dolphin can tell by listening what the object is – what kind of fish it is, how far away it is and how fast it is moving.
Hector’s Dolphin Reproduction
Hector’s dolphins mature at about 8 years old and they and they have a life span of around 15 to 18 years old. Females usually have one calf every 1 to 3 years. Hector’s dolphins mate in late spring and calves are born about a year later. The calves are 50 – 60 centimetres at birth and stay close to their mothers who provide them with milk and protection until they are old enough to fend for themselves, usually at about 1 year old.
Hector’s Dolphin Predators
Some sharks prey on Hector’s Dolphins.
Hector’s Dolphin Conservation
The Hector’s dolphin was given ‘threatened species’ status by the Department of Conservation in December 1999.