The Maui Dolphins - Will They Survive?

The Maui dolphin ( Cephalorhynchus Hectori Maui ) is the world's rarest marine dolphin. There are about 55 individuals left in the wild slowly but still declining, and they are an important part of New Zealand's natural heritage. Will they survive?

Habitat:

Maui dolphin live on the West Coast of the North Island, between Dargaville and New Plymouth in coastal waters off New Zealand. They are found close to shore in small groups less than 50m deep.  

Diet:

They eat small squid and fish such as flatfish, stargazers, cod and sprats on both bottom-dwelling fish and free swimming prey. The calves (babys) can live on there mother's milk for up to a year before eating small fish.

Size:

Adults measure between 1.2 - 1-7 m long, the males slightly smaller and lighter. The calves are 50 -60cm.

Threats:

Maui dolphin main threat is net fishing and trawling. They accidently get caught, not able to swim backwards then drown within minutes. Another threat is human pollution such as eating plastic bags that they mistake as jellyfish and try to eat, or deadly boat strikes; like a case in the South Island with a Hectors dolphins calve accidently getting hit and dying.

Their Cousin:

The Maui's dolphin cousin, the South Island Hectors dolphin look almost identical, but they are physically and genetically different. So how do you tell them apart? Maui dolphin have larger skulls and bigger rostrums (snouts) and distinctive grey, white and black markings. Maui and Hectors dolphins look different to other dolphins. They are the only New Zealand dolphin with a rounded black dorsal fin.Other dolphins usually have a sickle-shaped fin. Maui dolphin used to be called the North Island Hectors dolphin but since 2002 they have classified as a different subspecies.

The Hope:

There has been a ban on set netting and trawling along part of the North Islands West Coast. We can help too by reducing the amount of rubbish we put into our seas, support efforts to improve fishing gear, only buying seafood that is MSC (certified and spread the word about Hectors and Maui dolphins threat.

Conclusion:

With only 55 individuals left, these cousins of the Hectors dolphin may be gone within years, unless we step up and try to save New Zealands, North Islands, endemic dolphin.

Facts:

• They only live up to 20 years. This is a short lifespan compared to other dolphins and whales.
• Females have their first calf (baby) between 7 – 9 years of age.
• They produce just one calf every 2 - 4 years, making population increase a very slow process.
• Maui dolphin may only be able to grow their population by 2% a year. That means that a population of 55 can only increase by 1 individual per year.

• Maui dolphin are most likely to decline because they have short lifespans and are very slow to reproduce.