Why Maui's dophins are special
Maui’s dolphins (Cephalorhynchus hectori maui) are a sub-species of Hector’s dolphin (Cephalorhynchus hectori sp.), the world’s smallest dolphin. It is one of the world’s rarest dolphins and is found only on the west coast of the North Island of New Zealand.
The dolphin is listed internationally as ‘critically endangered’ (IUCN Red List) and as 'Nationally Critical' under the New Zealand Threat Classification System.
In 2012, a DOC-commissioned study estimated the Maui’s dolphin population to consist of 55 individuals aged more than 1 year (i.e. excluding calves under a year old). This estimate has a 95% confidence interval of between 48 to 69, meaning the researchers are 95% confident that the population lies within this range. See Maui's dolphin abundance estimate.
This small population of dolphins is thought to have been isolated from their more-numerous relatives, South Island Hector's dolphin, for thousands of years.
Maui's dolphin used to be known as North Island Hector's dolphin. However, research demonstrated the North and South Island dolphins are physically and genetically distinct from each other - see Geographical variation in Hector's dolphin. Since 2002 they have been classified as separate sub-species.
Adult and juvenile Maui dolphins seen during a survey, west coast of the North Island between Kaipara harbour and New Plymouth, 2009-2010
About Maui's dolphin
Maui's dolphin and common dolphin dorsal fins compared
Maui's dolphin are generally found close to shore in groups or pods of several dolphins. They are often seen in water less than 20 m deep but may also range further offshore. Their characteristics include:
- Distinctive grey, white and black markings and a short snout. Maui’s and Hector's are the only dolphins with a well-rounded black dorsal fin.
- Females grow to 1.7 m long and weigh up to 50 kg. Males are slightly smaller and lighter.
- The dolphins are known to live up to 20 years.
- Females are not sexually mature until 7 - 9 years of age. They produce just one calf every 2 - 4 years, making population increase a very slow process.
- Like other dolphins, Maui’s use echolocation to find their food. They send out high frequency ‘clicks’ that bounce off surrounding objects and fish, giving the dolphins a detailed picture of their surroundings. This sonar is not used all the time, which may be why the dolphins get caught in nets.
- Maui’s dolphins feed opportunistically, both at the bottom and throughout the water column, on a variety of species of fish.
Hector’s and Maui's dolphins are known to Māori by other names including tutumairekurai, aihe, pahu, popoto, papakanua, upokohue, tukuperu, tūpoupou and hopuhopu.
Maui's dolphin brochure (PDF, 5,570K)