"We were reliably catching them in the wild up until 2008 but there are no longer anymore there."
DoC supported by Ngā Manu are now trying to build a population that will eventually be able to be released into the wild on a predator free island.
Holding their annual survey yesterday, Ngā Manu staff were excited to find four juvenile Whitaker's skinks among their population.
Reserve manager Matu Booth said, "There was a lot of jubilation around the discovery because it is the first time that Whitaker's skinks have reproduced since arriving here three years ago.
"It is a significant boost to a very precarious population.
"We have found four young juveniles, and when you're talking about a population of what is now 42 in the region, any addition is important."
This takes Ngā Manu's population from 20 to 24, which added to Dennis' 18 makes 42 of the endangered skinks.
"This is a major milestone for Ngā Manu.
"'It's one of the projects that happens behind the scenes, unfortunately the public don't get to see it at all."
Along with providing a place for the public to view birds and other wildlife the objectives of the Ngā Manu trust are education, conservation and preservation of New Zealand native flora and fauna.
Taking on the role out the back of Ngā Manu away from the public, the reserve has been looking after the Whitaker's skinks, helping to bring the population back into a place where they can be released into the wild.
"A lot of what the public see is just the tip of the iceberg."
Helping with the survey at Ngā Manu was Wellington Zoo ectotherm keeper Joel Knight who was supporting the survey out of personal interest.
"It's unheard of for large crepuscular or nocturnal species of lizards to survive under heavy predation pressure like they did in Pukerua Bay.
"For theses skinks to survive in Pukerua Bay until the early 2000s is just preposterous.
"If we don't look after them, extinction is forever, we won't be getting them back."
Measuring the skinks from snout to the vent and vent to tail tip, the biggest measured was a female skink coming in at 202mm, weighing 23.81 grams.
Dave said, "They're all looking really good this year, they've put on more weight since our last survey.
"The breeding process is very slow, they live for a long time but only breed every few years."
With records showing the Whitaker's skinks living as old as 52 years, the recovery group are hoping when they eventually release them into the wild they will be able to release the founding stock with their young, having a mix of ages.
The only other record of Whitaker's skinks in New Zealand are in the Mercury Islands and the Coromandel Peninsula up north.
However with no DNA testing done on the skinks, Joel said there is a high chance they are not the same species.
"The DNA testing has never been done and there is a good chance they're actually a different species or at least a sub species which is why we're treating the Pukerua Bay site as its own entity.
"That's why it's so important that we look after them, if they go, we can't get them back."
About Whitaker's skinks
• Whitaker's skinks are able to live 10-50+ years
• They don't breed every year, on average they breed every second year
• They are named after Anthony Whitaker, a New Zealand herpetologist
• There is a population of 42 in captivity between Ngā Manu and private breeder Dennis Keall
• There are currently no suitable sites in the Wellington region to release the Whitaker's skinks that are pest free or do not have other more aggressive skinks that would wipe out the Whitaker