Native reptiles thriving on Tiritiri Matangi

While Tiritiri Matangi is a recognised conservation leader for a number of reasons, one of its lesser known, or less regularly observed, successes is in the area of its expanding reptile diversity complementing the Island’s broader biodiversity.

Tiritiri Matangi currently has seven species of reptiles, made up of three remnant (that is, already present, no translocation required) populations and four translocated under various DOC/ iwi-supported projects over the last 20 years. Each species occupies a unique niche, with indications that the populations are doing well and expanding.

Aotearoa/New Zealand’s native reptile species are unique for a number of reasons, including their range of colouration, breeding, being primarily live-bearing versus egg-laying, and therefore they are highly targeted by illegal smugglers, especially the various green geckos. Geckos usually give birth to only two young (neonates) a year, a slow replacement strategy increasing risks to their wellbeing and security.

Moko skinks (Oligosoma moco) and copper skinks (Oligosoma aeneum) are probably the most abundant species on Tiritiri Matangi with survey indications of 0.5-1.7 animals per square metre. These attractive, fast-moving skinks are often seen running across pathways, especially on warm, sunny days. As a remnant population, they are well established and spread across the Island. The easiest way to tell these species apart is that the copper skink, as the name suggests, is a speckled coppery colour whereas moko skinks are usually a bit larger and can be distinguished by stripes running the length of their bodies.

Raukawa gecko (Woodworthia maculata) are also a remnant population once thought to be absent from the Island. However, in 2003, around 10 years after the removal of the kiore rat population, they reappeared. First evidence was footprints identified in tracking tunnels. These geckos tend to hide in the rock crevices and, while initially found only on the eastern cliffs, they have recently been seen at the bunkhouse, the back of the Visitor Centre and down at Hobbs Beach.

An iconic New Zealand species, tuatara (Sphenodon punctatus) was introduced to Tiritiri Matangi in 2003 when a population of 60 animals – 40 females and 20 males – was translocated into four ideal bush locations. Tuatara are now regularly seen on the pathways and have spread out significantly.

Duvaucel’s geckos (Hoplodactylus duvaucelii) were first introduced to Tiritiri Matangi in 2006 (19 animals) and then a further 90 founders added in 2013. This is Aotearoa/New Zealand’s largest-remaining gecko species and can measure up to 320mm long. They’re primarily nocturnal and ground-dwelling, but can occasionally be seen basking during the day on flax plants. They are large, robust geckos that may be distinguished by a series of white spots down their backs. They often do not move when spotted, which allows a great opportunity to see one of the country’s very special reptiles.

Shore skinks (Oligosoma smithi) were introduced to the Island in 2006, with further individuals introduced in 2010, supplementing the population. These skinks are found on the shoreline in open habitats with driftwood, in rocky habitats, mat-forming vegetation or seaweed. They can reach up to 80mm long and can be speckled or occasionally black in colour.

The most recent project is the translocation of the Auckland green gecko (the elegant gecko, Naultinus elegans). These are very attractive and brightlycoloured green geckos, often with colour patches or stripes along the body. They can occasionally be found in a bright yellow colouration. They are diurnal or cathemeral, meaning they can be seen both at night and during the day. They’re difficult to spot but love to live in the mānuka or kānuka, where they feed on invertebrates and can often be seen licking nectar.

Tiritiri Matangi is fortunate to have such a diverse range of native fauna. Plans are under way to consider additional reptile species to complement those already on the Island, working in conjunction with iwi, DOC and other key stakeholders. Not only does this build on the richness and diversity of native life on the Island for future generations, but it also enables other future conservation options and habitats for our special and unique species.

Remember, all New Zealand’s native fauna are absolutely protected so if you are fortunate enough to catch a glimpse of one of these special animals, cherish the opportunity, observe how the animals behave in their natural habitat, but never touch or attempt to capture them.