The Hector’s dolphins are only found around the inshore waters of the South Island of New Zealand, with Akaroa Harbour and Banks Peninsula hosting the highest population in one location. They have a territorial range of 52 kilometres, never going far from where they are born.
There is also a sub-species of the Hector's dolphin, called the Maui dolphin, which is found in the North Island.
The Hector’s dolphin is distinguishable from other dolphins by their rounded black dorsal fin which is shaped like a Mickey Mouse ear. Their bodies are a distinctive grey colour, with white and black markings. They also have a short snout.
Hector's dolphins are classed as “nationally endangered” with their population thought to be around 10,000. Banks Peninsula hosts roughly 1000 of the Hector's dolphin population. There are as few as 55 Maui dolphins left.
Hector’s dolphins live to around the age of 20-25 years old, which is similar to us living until we are 85-90!
Adult Hector’s dolphins can reach up to 1.4 m in length, and weigh between 40-60kg, with the males being slightly smaller and lighter than females. At birth, Hector’s dolphin calves have a total length of around 60-80cm and weigh 8-10 kg, and look a little like a rugby ball with flippers.
Hector’s dolphins are not too fussy about what they eat, and hunt more to the size of the prey rather than actual species. They make frequent short dives to find food, such as flounder, red cod, crabs, kahawai, mackerel and squid.
The Hector’s eyesight is only slightly better than humans, so they use echolocation to judge distances, locate their prey, and judge how fast it is moving – it’s like seeing with sound. They do this by sending out high frequency clicking noises and when the sound strikes an object it bounces back, the dolphin can then tell by listening what the object is. In familiar areas, their echolocation is often ‘turned off’, which means they cannot always detect dangers.
Hector’s dolphins spend their day between feeding and play. They love to surf on waves, play with seaweed, and are incredibly friendly and inquisitive creatures, which explains why they like to get up close to boats - sometimes we wonder who is looking at who!
The Hector’s dolphin was named after Sir James Hector, who was the curator of the first Colonial Museum in Wellington (now named Te Papa). Sir James Hector examined the first dolphin specimen that was found. Sir James lived from 1834 to 1907, and was the most influential New Zealand scientist of his time.
The Banks Peninsula Marine Mammal Sanctuary in Canterbury was established in 1988, primarily to reduce set-net deaths of Hector’s dolphins in the area. The Marine Mammals Protection Regulations were introduced in 1992 to control marine mammal tourism activities.
Set-net controls were introduced to Canterbury in 2002 and on the West Coast & North Island in 2003.
DOC, in a joint initiative with the Ministry of Fisheries, developed a Draft Threat Management Plan released in 2007, which we here at Akaroa Dolphins were proud to be a part of. Since then additional fisheries restrictions have been implemented along with four new marine mammal sanctuaries, and alterations to the Banks Peninsula Marine Mammal Sanctuary. For more information on what is being proposed within the latest 2019 Threat Management Plan please visit our blog post by clicking here.