The Canterbury spotted skink has been reclassified as Nationally Critical. Photo: Supplied / James Reardon / Department of Conservation
One of New Zealand's rarest skinks is on the brink of extinction.
The Department of Conservation (DOC) has confirmed there are fewer than 1000 mature Canterbury spotted skink, and have reclassified them as Nationally Critical - the last step before extinction.
The reclassificaiton comes after DoC discovered populations of skink in the Ō Tū Wharekai Ashburton Lakes basin and surrounding ranges were not actually the same species.
"We thought there were secure populations of Canterbury spotted skinks in the Ō Tū Wharekai Ashburton Lakes basin and surrounding ranges, but recent DNA sequencing has proven these populations were misidentified and are in fact another type of related lizard," DOC technical advisor Lynn Adams said.
"This discovery means the Canterbury spotted skink's overall population is considerably smaller than our previous estimates.
"To make things worse, research on our monitored populations predict a 70 percent decline over the next thirty years in Christchurch, Banks Peninsula and Kaitorete Spit."
She said many of those populations were already functionally extinct.
"An exception to this worrying trend is the small but thriving population contained within a small predator-proof fence on Banks Peninsula, although the fence is subject to damage caused by earth movement."
Canterbury spotted skink's main predators are mice, hedgehogs, weasels, rats, stoats, and cats.
DOC said predator proof fences were considered the best medium-term way to protect the remaining skink populations while long-term solutions were found.