Story: Gannets and boobies
In an astonishing first flight, young gannets leave New Zealand and travel nearly 3,000 kilometres to Australia. Those that make it back seldom repeat the journey. Gannets have established huge coastal colonies where they breed and feed, catching prey with the deadly accuracy of their trademark plunge-dive.
Full story by Maggy Wassilieff
Main image: A pair of adult gannets
The Short Story
A quick, easy summaryRead the Full Story
Australasian gannets are beautiful big seabirds – snowy white, with a golden head, and black-tipped wings that reach 2 metres across. They live in colonies around the coasts of New Zealand and Australia, and their numbers are growing. They can live for 30 years.
Boobies are related to gannets, but there is only one New Zealand colony – the masked boobies of the Kermadec Islands.
Where do New Zealand’s gannets live?
Gannets breed at 24 places around the coast, including many islands. There are two colonies where people go to see thousands of birds up close:
- Cape Kidnappers. This rocky headland is in Hawke’s Bay. Birds started breeding here about 1880.
- Muriwai Beach. The first birds arrived here, near Auckland, from a nearby island in 1979.
In spring and summer the birds live in colonies, where they find a mate for life. Each pair has one chick every year. The pale blue egg is laid between September and December and both parents take turns sitting on the nest. After about six weeks the chick hatches. It is born without feathers, but in one month it has white fluffy down. Both parents feed the chick. By three months it is fat, with brown speckled feathers. Every day it stretches and flaps its growing wings.
At just four months of age, the young birds fly to Australia, nearly 3,000 kilometres away. This is remarkable because they have never flown or even found food before. Many die on this dangerous journey. After three years, the birds return as adults. Mostly they stay and breed in New Zealand.
To catch fish, gannets do a spectacular dive-bomb. They plunge head first into the sea, at up to 145 kilometres an hour. Their diet is mainly small fish such as anchovies and pilchards. There is plenty of food for them in New Zealand waters.
These large birds look like gannets, but their faces have a blue-grey mask-like pattern. They prefer warmer regions, and there is only one colony in New Zealand – about 200 breeding pairs of masked boobies breed on the Kermadec Islands, to the north.