The four animals ranged in size from 11 to 12cm and weighed between five and nine grams, meaning they were likely less than a year old.
Council parks and recreation manager Caroline Rain said the enclosure had been thoroughly searched prior to the tuatara being moved in February 2023, meaning the babies had likely been in egg-form at the time.
“We did everything you’d expect us to have done to ensure that there wasn’t anything there,” she said. “They were genuinely just missed, they were not seen.”
To elaborate however, although Zealandia has a fenced “scientific” enclosure for Tuatara near the front, there’s a separate group of them running wild around the rest of the sanctuary (though still inside the main fence). There’s a particular track up near the back of the fence with artificial burrows where they’re encouraged to hang out. You can often encounter them in the tracks near there, but it’s also completely possible to meet them effectively living wild anywhere else within the fence, and also not entirely uncommon.
But yeah they basically don’t live on the mainland outside fenced sanctuaries at all any more. Rats interfered too much that they were effectively gone from the mainland from some time after Maori arrival.
Ah I didn’t realise they were all through! I haven’t spent a lot of time there, we’ll probably go more when the kids are older.
I coincidentally went to a talk about it tonight where it was noted they’re getting so populous that there’s a new suspected risk of tuatara burrowing under the fence and letting something bad in.
The fence is due to be replaced within the next decade, and apparently they have tentative plans for an adjusted design to prevent this from happening.
I guess it’s a good problem to have.
Amazing that the tuatara burrowing is more of an issue than rabbits burrowing!
I just came across this document detailing the design of the fence, and was surprised to see it’s not very deep at all!
I had expected a deep fence going down a metre or so underground, instead it seems they went out - with a mesh buried 10-20cm that comes out from the fence so that digging animals are overtop of the mesh when they think to dig, and can’t dig through it. It makes sense now that burrowing tuatara could let animals in, as it would be much easier for an animal to dig out than for one to dig in.
