Researchers studying the New Zealand storm petrel have, for the first time since they were rediscovered nine years ago, found an egg of the critically endangered birds.

The petrels were presumed extinct then rediscovered in 2003, more than a century after the last sighting.

In February last year the birds were successfully tracked to breeding sites on Little Barrier Island in the Hauraki Gulf. Now scientists have discovered an egg.

NZ storm petrel project scientists took the opportunity when the female was off the nest to check the egg was fertile and record data, Department of Conservation principal science adviser Graeme Taylor said.


"It was exciting to see the egg of a bird once thought to be extinct."

Measuring a mere 31mm by 23mm, the egg was white with a fine dusting of pink spots at one end.

Storm petrel
Storm petrel

NZ storm petrels

• The seabird are sparrow-sized.

• They spend most of their lives at sea, coming ashore only to breed.

• They breed in burrows, are nocturnal when flying to and from their nest sites.

• They lay only one egg, which they incubate for more than a month.