Endangered gecko population starting to thrive in Bay of Islands

The new juvenile Duvaucel's geckos are doing well, and indicate the population is growing. Photo / supplied

A scheme to reintroduce New Zealand's largest lizard into the Bay of Islands is showing early signs of success.

In February 2018, 50 Duvaucel's geckos were moved from Mauimua in the Hen and Chicken Islands near Whangārei to their new home on an un-identified island in the Ipipiri chain.

The Project Island Song-led project brought the endangered species north for the first time in more than a century.

Since the reintroduction, continuous monitoring has been carried out on the island by volunteers.

It seems the population is growing, with seven young geckos identified during the last trip in February.

"The key thing here is wanting to re-find the adults released so we know they're surviving," Project Island Song lead Richard Robbins said.

"We released 50 so there's a broad spectrum of genetic diversity and we want to make sure that comes through into the new population.

"We're pleased with the number we've managed to re-find [adults] and the juvenile findings indicate the population is growing."

Project Island Song project manager Richard Robbins with one of Ipipiri's resident Duvaucel's geckos in 2018. Photo / supplied

Duvaucel's gecko is the largest living gecko in the country, and one of the biggest in the world, growing up to 30cm and weighing 120g.

They used to be found in large numbers across the North Island but, because of predators like rats, skinks and stoats, can now only be found at a few protected sites.

Project Island Song set up a network of monitoring stations across the island to help detect the adults and their offspring.

There have been two breeding seasons since the adults - 34 females and 16 males - were released, Robbins said. The females can give birth to one set of twins a year.

Though seven young have been identified, because the geckos are so well camouflaged, it's highly likely "there will be several more".

"I'm really optimistic,' Robbins said.

Seven young Duvaucel's geckos, including this one, have been spotted since the species were re-introduced to one of the Ipipiri islands in 2018. Photo / supplied

"It's still early days, so we can't say it's a success just yet. We need to keep monitoring for another 10-15 years until we know they've established as a new population.

"But we're heading in the right direction."

To date, six species have been reintroduced to the Ipipiri islands thanks to Project Island Song. Duvaucel's is the first reptile.

The others are all birds and include the toutouwai (North Island robin), pateke (brown teal), tieke (North Island saddleback), pōpokotea (whitehead) and kakariki.

Around 80 people attended the initial release of the Duvaucel's, including Robbins and representatives from the Guardians of the Bay of Islands, Te Rawhiti hapu, Ngāti Wai, Department of Conservation and NorthTec.

The next Duvaucel's gecko monitoring day is October 31. Email volunteer@projectislandsong.co.nz if you'd like to help.

Gecko facts

• Duvaucel's gecko [Hoplodactylus Duvaucelii] was named after French naturalist Alfred Duvaucel.

• Predation by introduced mammals led to a huge fall in numbers.

• Females do not lay eggs but give birth to live young.

• It is the largest living gecko in New Zealand.

• They can attain a total length of up to 30cm and weigh up to 120g.

• They can live up to 70 years.

• Duvaucel's are omnivorous. • They also eat nectar and native fruits so they help to pollinate native plants and distribute seeds.