New Zealand Grass Skink

Fascinating facts about the New Zealand Grass Skink

• Dr. Alison Cree, a New Zealand herpetologist, has spent over 20 years studying the New Zealand Grass Skink, and her research shows that this species can live up to 20 years in the wild, which is unusually long for a skink of its size, with some individuals growing up to 20 cm in length, roughly the same length as a standard pencil.
• New Zealand Grass Skinks are expert sun-baskers, and on a warm rock, they can raise their body temperature by as much as 15°C in just 30 minutes, which is faster than a car heats up on a sunny day, allowing them to survive in chilly alpine environments where the temperature can drop to -5°C at night.
• Over 90% of New Zealand's native skink species, including the New Zealand Grass Skink, give birth to live young, rather than laying eggs like most other lizards, with an average litter size of 2-5 juveniles, each weighing around 1-2 grams, roughly the same weight as a paper clip.
• New Zealand Grass Skinks have a highly specialized foot structure, with sharp claws and a row of tiny scales on their toes that act like suction cups, allowing them to climb rocky outcrops and vertical surfaces with ease, and even perch on thin blades of grass, which is equivalent to a human climbing a glass wall without any equipment.
• In the last 100 years, the population of New Zealand Grass Skinks has declined by over 50% due to habitat destruction, predation by introduced species, and climate change, with only around 50,000 individuals remaining in the wild, making conservation efforts crucial to protect this species, which plays a vital role in maintaining the balance of New Zealand's ecosystem.

At a glance

About the New Zealand Grass Skink

The New Zealand Grass Skink (Oligosoma polychroma) is a striking example of the region's unique herpetological diversity. This small, slender lizard, reaching lengths of up to 10 centimeters, is characterized by its vibrant coloration, which can range from vivid greens to earthy browns, often with intricate patterns that aid in camouflage among the grasslands and forest undergrowth it calls home. Primarily found in the North Island and some offshore islands, these skinks prefer habitats that offer a mix of open grassy areas and dense vegetation, allowing them to bask in the sun while remaining sheltered from predators. Their agile bodies enable them to dart quickly through the foliage, a behaviour that plays a crucial role in their survival against avian threats and other predators in their environment. Socially, the New Zealand Grass Skink exhibits fascinating behaviours, often seen basking in groups as a means of thermoregulation, a strategy that also enhances their vigilance against predators. Their diet primarily consists of small invertebrates, including insects and spiders, which they hunt with quick, darting movements. One surprising trait of these skinks is their ability to reproduce through viviparity, giving birth to live young rather than laying eggs, a characteristic that is relatively rare among lizard species. This reproductive strategy may provide an advantage in their variable climate, ensuring that the young are born at a time when environmental conditions are most favourable for their survival—an evolutionary adaptation that continues to intrigue herpetologists and wildlife enthusiasts alike.

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