Towns' Skink - a little known island resident

by Halema Jamieson

Environmental News Issue 30 Winter 2013
 

When we talk about lizards on Aotea/Great Barrier Island our beautiful, long and elegant chevron skink usually springs to mind. But Aotea actually has thirteen different species of native lizard making it one of the most diverse areas for reptiles in the country.

One of the lesser known lizards found on the island is the Town’s skink (Oligosoma townsi). They were first discovered on Aotea in the early 1980s and at the time were thought to be marbled or Oliver’s skinks (Oligosoma oliveri). However, a closer look at their genetics in 2008 revealed that they were in fact something even more special. Unlike the more widespread marbled skink they belonged to a new species of lizard confined to just a handful of offshore islands. They were subsequently named Towns skinks after Dr David Towns, a prominent New Zealand herpetologist* who actually lived at Kawa, in the north of Aotea, as a young boy. 

The Town’s skink is a medium sized lizard (approx 87mm SVL) that lives amongst leaf litter and rock crevices in coastal broadleaf forest, only coming out at night to feed. Because of this they are highly susceptible to predation from rats and cats. All of the few islands where they have survived are free of rodents and cats, except for Aotea. As a result, they are extremely rare here and are only known to be hanging on in two small isolated patches.

A recent survey of these sites turned up just three Towns skinks. All had regrown tails which may be indictative of a run-in with a cat or a rat. Both areas also had noticeable rat sign with lots of rat droppings and rat teeth marks on plastic lids left over winter at the sites.

Hopefully its not too late for these lizards on GBI but without proper predator control their days here may be numbered.