Thirty more tuatara are settling into their new home at Orokonui Ecosanctuary.
They joined 44 wild adults and juveniles which had arrived three weeks ago from Stephens Island, in Cook Strait.
The new arrivals were captive-reared juveniles from Nga Manu Nature Reserve at Waikanae.
Their arrival brings the total number of tuatara at Orokonui to 89, including 15 juveniles that had been raised at an enclosure within the predator-proof fence at Orokonui, 13 of which were also released this week.
Ecosanctuary general manager Chris Baillie said the release of the tuatara into specially prepared burrows inside the fence went really well.
Before their release, transmitters were attached to some of the tuatara, mostly females, so researchers could keep track of where they were nesting.
The two groups would be kept separate initially while comparative studies of their dispersal patterns were undertaken by scientists from the University of Otago, she said.
Readings from the transmitters on the Stephen's Island tuatara showed one had already moved 800m from its release site.
"They're exploring their new home and finding new places."
Orokonui trust board chairman Neville Peat said because Orokonui was the southernmost location for free-roaming tuatara, there was a good deal of scientific interest in seeing how they adapted.
"The release sites are well away from the public walking tracks so that the tuatara will not be disturbed," he said.