One of the four rare white humpback whales recorded in the wild has been sighted in Cook Strait, New Zealand, during the annual whale survey.

The Conservation Department believes the albino is "Migaloo" who has come from the eastern coast of Australia. First spotted in 1991, he is believed to have fathered two other albinos.

The fourth albino humpback has been sighted in the waters off Norway.

Male humpbacks travel long distances from their cold, nutrient-rich polar feeding grounds to the tropics where they mate.

The white humpback was spotted with a black humpback on Sunday (5 July), during the Conservation Department's 12th annual Cook Strait whale survey.

Whale survey leader Nadine Bott said distinctive features like the dorsal fin shape and spiny protuberances behind clearly pointed to Migaloo.

A skin sample, taken from the whale with a biopsy dart, would be compared with Migaloo's DNA to confirm the identity.

"The analysis will also identify whether the whale is albino or whether its whiteness is due to colour variation," she said.

The annual whale survey is timed for humpback whales' northern migration from the Antarctic to the South Pacific for breeding.

Into the fourth week, the latest survey has counted 122 humpback whales compared to 106 humpbacks in 2012, implying the humpback was on a comeback in the region.

Spanning 40-50 feet in length, the whales are named after the distinctive hump in front of their small dorsal fin.

They are most famous for their songs, which travel for great distances through the world's oceans. The sequences of moans, howls, cries and other noises are complex and often continue for hours on end.

Mothers and their young swim close together, often touching one another with their flippers in gestures of affection.

Females nurse their calves for almost a year. Calves do not stop growing until they are ten years old and the average life expectancy of the largest mammal is 45-50 years.

There are over 60,000 humpback whales world-wide, according to the World Wildlife Fund.

Humpback whales were an endangered species till 1988, but they have now recovered after commercial whaling bans.