Dozens of tuatara to be released at Brook Waimārama Sanctuary in Nelson

Tuatara are due to be released at the Brook Waimārama Sanctuary in Nelson on Wednesday afternoon, the first mainland translocation of the reptiles in the top of the South Island.

Operations manager Nick Robson said 56 tuatara will find a new home inside a 3.7 hectare mouse-free enclosure within the sanctuary.

He said staff and volunteers had spent the last year preparing for the release and had worked closely with Ngāti Koata. The iwi are kaitiaki of the species due to their ancestral links to Stephens Island / Takapourewa in the Marlborough Sounds, which is home to the world's largest tuatara colony.

"Tuatara has always been one of those species we planned to get back but it has taken quite a while to get to this point.

"These are the first tuatara to come back onto the mainland in the top of the south so it is a very big event for the sanctuary but also a very big event for Ngāti Koata."

Robson said volunteers had built a 500 metre mouse-proof fence, cut extra monitoring tracks, removed invasive weeds and drilled burrows for the tuatara to live in.

"It is very hard to keep mice out, they can get through a 7mm gap so it had to be a very well constructed fence to make sure that wouldn't happen but it's been free of mice since February so we are confident the tuatara will be safe in there."

Most of the tuatara have come from captive populations raised at Natureland, Wellington Zoo and Wildbase Recovery in Palmerston North, and the West Coast Wildlife Centre with some of the oldest tuatara from Stephens Island / Takapourewa.

"The youngest ones are a year old, so they are about 10-15 centimetres long and then we've got some older ones, fully grown that are in their thirties."

Robson said the tuatara travelled in postal tubes and were flown by Air New Zealand, to Nelson. They will be released in different parts of the enclosure, as larger tuatara were known to eat smaller animals.

An Otago University student would be monitoring the tuatara population intially, to see how they settle in, with the sancutary team to take over the ongoing surveillance, in the hopes the reptiles would breed in the coming years.

Robson said giant carnivorous land snails, or powelliphanta and Aotearoa's rarest parakeet, the kākāriki karaka have also been released in the sanctuary in recent years with great success.

The next on the list for reintroduction are little spotted kiwi and South Island kākā.