A recent survey of skink numbers shows the work is urgent and the fence, near Reefton, will be built earlier than planned to ensure the species’ survival.
Protecting a 5ha area, the fence will be constructed from a durable stainless steel mesh specially designed to keep mice, rats and stoats out.
Department of Conservation (Doc) ranger supervisor Gemma Hunt said the fence would hopefully stop the population’s decline.
"Even though we reduced mouse numbers earlier this year through pest control, there has been a constant threat of mice reinvading from outside the treatment area and continuing to prey on the skinks," she said.
"Long-term population monitoring by Doc and Auckland Zoo indicated there were between 40 and 100 skinks early last year, but more recent estimates suggest a worryingly low number of just 30.
"We hope to find more skinks when we continue our surveys this spring but in the meantime a predator-proof fence is necessary to secure the population and prevent extinction.
"Following the pest control operation earlier this year, we decided to move some skinks to safe housing at Auckland Zoo as a precaution," Ms Hunt said.
Doc and zoo staff managed to find three skinks in late autumn before cooler temperatures prevented further collection and these were transferred to the zoo.
"When it’s cold, the skinks burrow into the ground to protect themselves from extreme low temperatures and move very little. This not only makes it harder for us to find them but makes them easy prey for mice, who can access these same burrows," she said.
"New Zealand has one of the highest rates of threatened species in the world, with 4000 species, including the Alborn skink, at risk of extinction. Once these species are gone from here, they are gone for good."
Other populations such as Kapitia skinks were doing well in the fenced enclosures Doc had built, she said.
It is believed two or three baby skinks are born to females each year so, if those families can be protected from predators, their numbers will steadily grow.
The Alborn skink was discovered in the 1990s and has been rarely detected since. Not much is known about them although they are extremely tolerant of moist habitat.
Ms Hunt said the aim was to complete the $700,000 fence by November.
"We’re asking the public to support our work through donations to the New Zealand Nature Fund."— APL
