Hector's Dolphin

The Hector's dolphin is only found off the coast of New Zealand, which means it is endemic to New Zealand.

The Hector's dolphin is the rarest dolphin in the world - not a title to envy!

What's a dolphin?

• It's a mammal - they need air to breathe and their young suckle for milk.
• Dolphins are not porpoises.
• it is a cetacean - a cetacean is a creature belonging to a group of water living mammals having no hind limbs and a blowhole for breathing, including toothed whales, dolphins and porpoises.

Is it a Hector’s dolphin?

It may not be easy to tell which dolphin is ‘flying’ by when you see them from the shore or from a boat, so here’s some help…

The Hector’s dolphin is much smaller than other dolphins seen in New Zealand waters. An adult Hector’s dolphin grows to a length of 1.2 to 1.4 metres, compared with 4 metres for the bottlenose, 3.4 metres for the striped dolphins and the Dusky dolphins 2 metres. Also, the Hector’s is a little rounder than other New Zealand dolphins.

The Hector’s does not have a bottle-shaped snout. The forehead of the Hector’s 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 species of dolphin found in New Zealand waters have crescent shaped fins that are more pointed than the Hector's.

The colour scheme of the Hector’s dolphin is well defined with areas of grey, black and white.

The sides of the head, the flippers, dorsal fin and the tail are all black. The belly is white except for a small area between the flippers. There is also a distinctive finger-like swoosh of white that extends from the belly, along the flanks towards the tail. The rest of the body is grey.

• The scientific name for the Hector’s dolphin is Cephalorhynchus hectori
• Hector’s dolphins are members of the family delphinidae, of which there are 32 species worldwide.
• The Hector’s dolphin is the smallest in the delphinidae family and the smallest sea-living dolphin, as well as the rarest oceanic species.
• Female Hector’s dolphins are usually 1.2 – 1.4 metres long and weigh about 45 kilograms, males are a little smaller and weigh about 10 kilograms less than the females.
• Of all the dolphins seen in New Zealand waters, Hector’s dolphins are the only ones with a rounded dorsal fin (shown in the diagram above).
• 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.
• They use echo-location to locate their prey – it’s like seeing with sound. 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. That’s pretty clever!
• In familiar areas the dolphins will travel with their echo-location 'turned off'
• The Hector’s dolphin was given ‘threatened species’ status by the Department of Conservation in December 1999.

North and South Island Populations

There are only about 3000 - 4000 South Island Hector's dolphins.

A small population of Hector's dolphins live off the coast of the North Island, mostly between Kawhia and Muriwai. They are the North Island Hector's dolphin, also known as the Maui dolphin. There are only about 100-150 North Island Hector's dolphin.

There are at least three genetically distinct populations of the dolphin, one on the west coast of the North Island and in both the west and east coasts of the South Island. The Southland population may also be genetically distinct.

The North Island and South Island Hector's dolphins are separate subspecies, they are physically and genetically different.

Click here to see a large version of this map

Life, play and babies...

Hector’s dolphins like to have company. They usually swim in groups of between 2 and 12 dolphins.

Hector’s dolphins tend to hang-out in the same area for many years and sometimes for life. They spend their days swimming along the coastline, surfacing to breathe, diving to find food and playing.

Dolphins love to play – and it’s wonderful to watch! Dolphins spend a lot of time playing. They play in the surf and use leaves and seaweed as toys. They are also interested in human activity. Dolphins will swim over to investigate people swimming, in kayaks and boats.

They like to swim beside kayaks and in the wake of boats. Hector’s dolphins seldom jump clear out of the water but when they do their jumps are very high compared to the long horizontal jumps of many other dolphin species.

Hector’s dolphins mature at about 8 years old and they live to around 15 to 18 years old.

Females usually have one calf every two to three years. Hector’s dolphins mate in late spring (New Zealand spring = September/October/November) and calves are born about a year later.

The calves are 50-60cm 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 one year old.

Dolphins in Danger

The Hector's dolphin is an endangered species and needs our help to keep them safe. In the ocean they face many dangers.

• Set nets/set nets are the biggest threat to the dolphins.
• As well as being in danger from drowning in set nets, Hector's dolphins have a low birth-rate, which means that their population does not grow quickly.

• Trawling, another type of fishing, is also a threat to dolphins.
• Some dolphins are harmed or killed by reckless boat users who are not careful in waters where dolphins live.
• Marine pollution also poses a threat to dolphins. They may accidentally eat rubbish, such as plastic bags, or get caught in it. Polluted waters may also make dolphins sick.

• Do not litter – rubbish can easily make its way to the sea where a dolphin may get tangled in it or mistakenly think it is food and eat it – Yuk!
• Make sure only water goes down storm water drains – keep pollutants out of the ocean!
• If you visit the beach and see some rubbish, please pick it up and put it in the bin so it doesn’t go in the sea.
• If you are in a boat when you spot dolphins, slow down and avoid turning suddenly. Never reverse the boat when you are near dolphins. Do not harass dolphins, if they move away from your boat, please leave them alone. Accelerate slowly when you are moving away from dolphins.
• Write to the Minister of Fisheries, tell them why you believe it is important that set nets be banned from areas where Hector’s dolphins live.
• If you ever see a dolphin stranded on the beach call the Department of Conservation (DOC). Even if you get to the dolphin too late and it has died, still call DOC because the dolphin's body may help scientists learn more about the species and why it died.
• Tell a friend to read this web page – then they will learn how to care for the Hector’s dolphin too!

More Hector's dolphin pages - Set Nets | Map | Protection | Resources

The Hector's dolphin information was updated in October 2003.