The vulnerable Pedra Branca skink has a remarkably restricted distribution, being only found on the barren, widswept island of Pedra Branca, where they feed on small invertebrates and on fish scraps dropped or regurgitated by the seabirds on the island. They are susceptible to any changes in the seabird colony.
Pedra Branca skinks are the only species of lizard recorded from Pedra Branca. Adults have a head and body length of 6-10 cm and a weight of about 14 grams. Pregnant female skinks can weigh up to 22 grams. Juveniles are more lightly coloured than adults, which may be a glossy charcoal colour.
Pedra Branca Island is thought to have been separated from mainland Tasmania for at least 15,000 years. There are six separate colonies of Pedra Branca skinks on the island. These lizards shelter in deep crevices and cracks which provide essential protection from wind, salt spray and even waves. Adult skinks will fiercely defend their burrows against intruders. They are active only when air temperatures are above 15°C. Most of the food of this species consists of small invertebrates like insects, spiders and isopods, but the species also feeds on fish regurgitated from seabirds and seabird eggs. These foods are only available to the Pedra Branca skink on a seasonal basis. The movement of silver gull colonies into areas where the skink is living on the island has recently lead to the rapid decline of some lizard colonies. This species is dependent upon the seabird colonies on the island and is subject to population fluctuations from about 250-600 individual lizards. Pedra Branca skinks are a long-lived species. They mature at about 6-8 years of age and can live at least ten years, possibly as long as 15 years.
Like most endemic Tasmanian skinks, the Pedra Branca skink is live bearing.
Found only on the small island of Pedra Branca, about 26 km south of the southeast tip of Tasmania. Pedra Branca, which is about 55 m above sea level at its highest point, has a total area of about 2.5 ha but only about 0.14 ha provides suitable habitat for this skink.
Vulnerable. For full details, see our threatened species pages.
Pedra Branca skinks face a number of potential threats, including the introduction of rats or other animals to the island, climate change, an increase in the number of silver gulls which feed on the skinks, or loss of food source through a decline in seabird colonies.