The first cahow chick of 2025 has hatched — the earliest in at least 25 years — in what is hoped to be a record-breaking season.

In a post on the Nonsuch Expeditions blog, Jeremy Madeiros, the Department of Environment and Natural Resources’s principal scientist for terrestrial conservation, said that the bird was first spotted on Wednesday.

“This chick was found in the R833 nest at the ‘A’ cahow nesting colony on Nonsuch, and was already several days old, having been fed at least two to three times by the adult birds,” he noted.

“Cahow chicks have a weight of 28g to 38g at hatching and this chick was already fat and healthy, weighing 68g, which cahow chicks typically do not reach until they are at least four days old.”

Mr Madeiros said the bird is likely to have hatched on February 15 or 16, beating the previous earliest hatch date over the past 25 years of February 18.

He said the parents have nested together on Nonsuch since 2012, with the male of the pair being the first cahow chick moved to Nonsuch in 2008, the fifth year of the translocation project.

“This chick was fed daily on fresh anchovies, provided by Chris Flook, and squid with vitamin supplements for 17 days, and I actually observed it during a night watch fledging out to sea on the night of May 24 at 11.54pm, from the cliff edge at the ‘A’ colony site in a steady light rain,” Mr Madeiros recalled.

“This bird was discovered on its first return as an adult four years later on November 15, 2012, when it was discovered in the R833 burrow, where it has nested ever since.”

The female of the pair, meanwhile, was a non-translocated bird that was first banded as a fledgeling in 2006 and later found as an adult on Nonsuch island in 2011.

“This pair have nested together for 14 years, since 2012,” Mr Madeiros said.

“They are not a particularly successful pair, before this year they have only produced three successfully fledging chicks, in 2014, 2016 and 2018, then had unsuccessful nesting for six years.

“Including this new chick, they have produced only four chicks in 14 years.

“However, despite this, at least two of these chicks have returned and are breeding successfully, one on Nonsuch Island, and one on Horn Rock, so they are still contributing to the recovery of the cahow population.”

Mr Madeiros added that two other eggs were found this week to be “pipping”, indicating that they were in the early stages of hatching, while at least half a dozen other eggs were “very close to beginning to hatch”.

J.P. Rouja, the founder of Nonsuch Expeditions, added: “If the majority of the 30-plus chicks in currently viable eggs on Nonsuch survive through to fledging, we should easily break last year’s record of 25.”

He urged the public to get a glimpse of cahow life through the Nonsuch Expeditions CahowCam2, where it is expected that a chick will hatch around March 7.

Cahows, also known as Bermuda petrels, were largely wiped out by introduced predators and hunting by early English colonists.

By the 1620s, the species was believed to be extinct.

However, it was rediscovered in 1951, with a handful of the birds found nesting on four rarely visited rocky islets, which sparked efforts to rebuild the population.

As part of the project, man-made burrows were created on Nonsuch Island, with chicks translocated to the island in the hope that they would return to Nonsuch as adults.

The project has borne fruit, with a growing number of birds fledging on the island and, for the first time since the 1620s, a cahow couple in 2023 successfully dug its own burrow and raised a chick inside it.

A total of 76 cahows successfully fledged last year, including 25 birds on Nonsuch Island.