Ōi / Grey-faced petrel
Ōi: Hunters of the high seas
Ōi (Grey-faced petrels) are one of the few burrowing petrels to still survive on the New Zealand mainland.
Habitat: Offshore islands across the North Island of Aotearoa and coastal headlands across the upper North Island.
Breeding season: March - January
Diet: Squid, fish and crustaceans.
What’s their superpower?
With their metre-long wingspan and wildly impressive navigation and foraging skills, ōi (aka grey-faced petrels) spend most of their lives gliding over the open sea. They can reach speeds of up to 100km per hour and fly for thousands of kms at a time searching for food for themselves and their chicks.
Why do we need them?
By feeding at sea and nesting on land, these seabirds bring ocean nutrients back to shore. They help fertilise forest soils which is great for plant growth and other animals. Their burrowing lets air into the soil which keeps it healthy, and because they’re sensitive to changes in the ocean, they can act as early warning signs that the ecosystem is out of whack.
Did you know?
Most of their prey, including squid and crustaceans, are bioluminescent, meaning they glow in the dark. When hunting at night, ōi use this natural glow like a spotlight to locate and catch their next meal.
Fascinating facts
Saltwater sippers: Ōi drink straight from the sea. A special gland above their beak filters out the salt so they stay hydrated on long-haul flights.
Burrow builders: They build their nests in cosy underground burrows, usually tucked beneath tall coastal forests or in grassy spots near sea cliffs.
Fatty flight fuel: Their seafood snacks turn into a rich, waxy oil stored in their stomach. This acts like an energy drink, powering adults through long-distance flights and sustaining chicks with high-fat meals through regurgitation.
Sticky business: When threatened, ōi can spit this foul-smelling stomach oil at predators. Not only does it stink, it clings to enemy feathers, messing with waterproofing - taking hours to clean.
Courtship chaos: Breeding colonies burst into life during mating season with loud calls and spectacular aerial chases as ōi show off and connect with mates.
Super sniffers: They have special tube-shaped nostrils that give them a superpowered sense of smell. It helps them sniff out food across the ocean and even find their own burrow in a crowded colony, all in the dark.
Conservation corner
Ōi are making a comeback and are now classed as Not Threatened by DOC. Predator control on key breeding islands has helped clear pests like rats that gobble up eggs and chicks. But they’re not completely out of the woods and still need our help to continue to thrive.
How you can help
Keep dogs close and under control when walking near coastal areas. Even the friendliest dog can disturb nesting birds.
Keep cats inside at night and have them desexed to reduce the number of predators around nesting sites.
Set traps in your backyard to help control pests like rats, stoats and ferrets.
Volunteer for a local trapline or predator control group.
Switch off or dim outdoor lights (or use sensors) if you live near the coast.
Help us to help the Ōi / Grey-faced petrel
Endemic to the North Island ōi will mostly hunt squid, fish and crustaceans at night. It is thought they use light cues to spot bioluminescent prey, and they can travel up to 600km to feed their offspring. Town lights, however, disorientate these birds and result in crash landings. Once grounded, they are stuck as they're not suited to take off from the ground.
Ōi have made a comeback due to extensive predator control, but with over 75% of our indigenous species at risk of extinction*, the Pest Free Waitākere Ranges Alliance is raising funds to help defend these, and the many other special species of the Waitākere Ranges.
Thank you for your support of this awesome petrel!
Cornwallis / Ōi / Grey-faced petrel Supporter Gear
Support the conservation efforts of Pest Free Waitākere Ranges Alliance!
By shopping with us, you're contributing to the protection and preservation of our ngahere, and supporting our vision of a restored and thriving Waitākere Ranges.
Choose from a range of clothing and accessories printed with our exclusive design by local artist Jay Linden featuring Cornwallis' special species – the Ōi / Grey-faced petrel.
Find out more
Image credits: Grey-faced petrel in flight by Shaun Lee • Grey-faced petrel on nest by Genevieve Early • Fern by Toby Hall on Unsplash
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