Seabirds – Grey-faced Petrel

This medium-sized, all-dark petrel with a pale face is one of the few burrowing seabirds to have survived on New Zealand’s main islands, albeit in small numbers. It is about the size of a red-billed gull, but with longer wings and large deeply hooked bill. There was a vast population of such seabirds breeding here before humans arrived on our shores; now only tiny remnants remain.

The grey-faced petrel is a New Zealand endemic species, meaning it breeds nowhere else in the world, and only in northern New Zealand. However, despite it breeding on most islands in the Hauraki Gulf, and at places on or close to the mainland like Tawharanui, Goat Island and Bream Head, it is not commonly seen during the day from a boat, unless you are a long way offshore. These birds feed out past the continental shelf edge. In fact, on a voyage to the Kermadecs in October two years ago, they were the most common seabird I saw all the way up and back. Their prey is mostly squid, caught mainly at night; also, crustaceans and fish.

They are a winter-spring breeder (April to December) and, like all petrels, come to land only during breeding, either to share incubation duties with their mate, or to feed their single chick. They are also nocturnal over land, so it’s only at dusk that you first see them flying over a headland or an island. They have two pronounced calls: one is like a high-pitched whistle, almost like a squeaky wheel, the other a drawn out ‘oi’ call, with the latter being the origin of its Maori name, ‘Oi’.

At sea, they are dynamic as they fly, with a high, arcing flight, which is very pronounced in strong winds. I can remember during one trip up to the Far North, we took shelter during a big storm close in under North Cape. During the day, we watched in awe as these petrels streamed past us in numbers, many of them lifting effortlessly high over the rugged cape and its lighthouse, using it a short cut as they made their way from one feeding ground to another. They can cover large distances in their quest for food, with some birds recorded flying to the east coast of Australia while their partner was sitting on their egg on Auckland’s west coast.

The grey-faced petrel is a target species for restoration projects, and they are increasing in numbers at Tawharanui Open Sanctuary since a pair was found nesting back in 2009; living proof of the importance of eradicating predators, and making sure there are enough reserve areas for us to share our world with these very special wild creatures.