What does it look like?
Rainbow skinks are 3-4cm long from the tip of the nose to hind legs, excluding the long thin tail. They are brown or grey-brown with a dark brown stripe down each side, and an iridescent rainbow, or metallic sheen, when seen in bright light. They look very similar to native skinks but rainbow skinks have one large scale on the top of their head, and native skinks have two smaller scales.
Rainbow skinks prefer moist areas and are commonly found under vegetation, litter, rocks and logs. They also thrive in urban areas, gardens, commercial areas, industrial sites, garden centres, and waste ground. They will frequently enter freight and shipping containers. They are known to be well established in the greater Auckland area, Coromandel Peninsula, Tauranga, and Te Puke. Populations are also present in the Waikato region and in Northland.
Why is it a problem?
Rainbow skinks can reach high population densities in a relatively short time, competing with native lizards and other native fauna for food and habitat, and increasing predation pressure on native invertebrates. Rainbow skinks breed rapidly but most native skinks are long-lived and only breed once per year. Some don’t even start breeding until they are around five years old.
Rainbow skinks reproduce rapidly – laying up to eight eggs three times per year (more than five times as fast as most native lizards). They also mature in less than half the time of native lizards.
Rainbow skinks are mobile animals and are also transported by human activity. For example, in household items, mail, personal effects and shipping containers. Plants and potting mix from nurseries have also been found harbouring skinks and eggs.
If you live in an area that has plague skinks, and wish to relocate any equipment, goods, or other freight to an area that is free of this species; thoroughly check your personal belongings for plague skinks before departure.
Potting mix in potted plants is a favoured breeding habitat. Check these for any of the small white eggs, especially if plants are to be used in restoration projects, such as on off-shore islands or key ecosystems on the mainland.