Ōi | Grey-faced Petrel

Ōi are medium-sized burrow-nesting seabirds. Before the arrival of mammalian predators probably many hundreds, if not thousands, would have nested along the cliff tops in what is now the Park. A few pairs of these long-lived birds may have survived the predators, but they are unlikely to have raised chicks. These birds only come to land in the relative safety of darkness. Their natural burrows are up to 3 metres long and provide suitable conditions for reptiles and invertebrates which share them with the birds. When they fly close to land at night they can be recognised by their flight calls which sound a bit like a squeaky gate.

At night, in red torch light, a close-up of a grey-faced petrel in the hands of a volunteer.

Once the pests were removed, we started night-time broadcasts of Ōi calls using solar-powered loudspeakers and provided wooden nest boxes dug into the ground. Somewhat unusually for New Zealand burrow-nesting seabirds, Ōi don’t seem to be determined to return to the colony where they hatched. Young birds wander widely over hundreds of kilometres visiting other nesting sites before they choose one and find a partner. This wandering increases the possibilities of attracting birds to the Park and we have had some success.

At night, three volunteers wearing warm clothes and headlamps are banding the legs of a grey-faced petrel.
Banding an Ōi/Grey-faced petrel

On dark mid-winter nights our seabird enthusiasts visit the colony hoping to catch and band prospecting birds and have sometimes caught as many as thirty. Several pairs are now nesting in the wooden boxes and others in natural sites.


Ōi lay just one egg each season around July which hatches after 55 days and the chick will fledge around December or January. Most young birds will not start breeding until they are eight to ten years old, but they can survive and breed for another thirty years.

We have also managed to attract a few pairs of pakahā/fluttering shearwaters to nest in the boxes.