Oligosoma "Whirinaki"

Whirinaki skink

Oligosoma "Whirinaki"

Whirinaki skink basking on forest floor (Whangarei, Northland). <a href="https://www.instagram.com/nickharker.nz/">© Nick Harker</a>
Image attribution
Whirinaki skink basking on forest floor (Whangarei, Northland). © Nick Harker
Herpetofaunal category
NZ Skinks
Species complex
Conservation Status
Threatened - Nationally Critical
Common names
Whirinaki skink,
Bream Head skink.

Length: SVL up to 70mm, with the tail being longer than the body length

Weight: unknown

Description

Whirinaki skinks are a distinctive and bold little skink which eluded discovery until relatively recently. Similar in appearance to the closely related glossy brown skink (Oligosoma zelandicum), Whirinaki skinks have brown dorsal surfaces sometimes with lighter and darker flecks, and a pale dorso-lateral stripe extends just past the forelimb. On the flanks, a broad dark-brown lateral stripe is bordered below by a light-cream stripe that breaks up beyond the forelimb. Their ventral surface is speckled and may be light-brown or deep red-orange. The head is short and blunt, with a distinctive tear-drop under the eye. Whirinaki skinks also have a prehensile tail which aids in climbing.

Life expectancy

Unknown.

Distribution

Whirinaki skinks have a disjunct distribution. They were originally discovered from a single specimen found inside a hut at Whirinaki forest in the central North Island, then subsequently detected at Bream Head Scenic Reserve in Northland (over 350km north from the original sighting).

Ecology and habitat

Whirinaki skinks are bold and strongly heliothermic. They occur in forest and scrub, where they can be seen basking on or near to the ground in forest clearings. Whirinaki skinks are mainly terrestrial, but are adept climbers and may be found basking above-ground on tree trunks and low vegetation.

The individual from Whirinaki forest was found inside a hut, located within podocarp, tawa and silver beech forest. The population at Bream Head occurs in clearings within coastal broad-leaved forest, scrub, and on rock outcrops.

Breeding biology

Unknown.

Diet

Little is known about the diet of Whirinaki skinks. They feed on small invertebrates, and presumably the berries / fruit of native plants, in common with other species of New Zealand skink.

Disease

Unknown.

Conservation strategy

Extensive predator control is undertaken at Bream Head (the northern population for this species).

Repeated surveys at Whirinaki forest in the vicinity of where the species was first discovered have failed to detect further individuals.

Interesting notes

Whirinaki skinks are part of a clade which includes their sister taxon the glossy brown skink (Oligosoma zelandicum), as well as the chevron skink (O. homalonotum) and striped skink (O. striatum).

References

Hitchmough, R.A., Barr, B., Lettink, M., Monks, J., Reardon, J., Tocher, M., van Winkel, D., Rolfe, J. (2016). Conservation status of New Zealand reptiles, 2015; New Zealand threat classification series 17. Wellington: New Zealand Department of Conservation.

Jewell, T. (2011). A photographic guide to reptiles and amphibians of New Zealand. Auckland: New Holland Publishing.

van Winkel, D., Baling, M. & Hitchmough, R. (2018). Reptiles and Amphibians of New Zealand: A Field Guide. Auckland: Auckland University Press, 376 pp.