Cobble skink conservation
Cobble skink (Oligosoma aff. infrapunctatum "cobble”) was first discovered in 2007, and only known from a tiny beach north of Westport.
The species looks very similar to the closely related speckled skink, found in neighbouring habitat. Cobble skink had been overlooked by herpetologists because of this similarity.
Despite the looks, cobble skinks are very different from other species. They prefer the deep cobble habitat found immediately above the high tide mark, and appear to be adapted to wriggling through the spaces between cobbles.
When first discovered cobble skinks were restricted to a tiny area but were apparently abundant there. It's likely the deep cobble structure protected them from introduced predators, which were impacting on skink populations outside of this specialist habitat.
Eight years after discovery, the skink population had declined significantly due to loss of habitat from coastal erosion.
Cobble skinks were assessed in late 2015 as Nationally Critical, because they occupied less than 1 ha of habitat and had undergone a severe decline.
Predation and habitat loss
Very little is known about this species. It’s expected that mice is a significant predator, but rats, mustelids, cats, and the native weka will also be preying upon skinks.
Climate chance, storm events and rising sea levels are likely to have significant impacts. More frequent and intense storm events erode their preferred habitat above the high tide line.
Coastal development and coastal erosion protection works destroy habitat, as do vehicles and fire.
Imminent storms and ongoing erosion of their tiny habitat led DOC to carry out an emergency salvage operation in the winter of 2016. As many as possible of the remaining skinks were collected and flown to Auckland Zoo.
The 36 skinks rescued, perhaps the entire remaining population of this species, have successfully established in captivity, and zoo keepers are optimistic they will breed.
DOC and Auckland Zoo are working together to return these precious West Coast endemics to their natural home. We need to find suitable habitat safe from predators and coastal erosion, as well as a large local semi-captive facility.
The future for this species is still uncertain. Once numbers build within the semi-captive facility, skinks will be released to wild cobble habitat to establish new populations along beach front habitat.
You can help
Beach ecosystems are fragile and often contain important and secretive species. Avoid driving on the beach, lighting fires, or removing driftwood to help protect these areas.