The first tuatara eggs to be found at Wellington Zoo in more than 20 years could hatch at any moment.
Staff say the eight eggs, now nestled safely in incubation containers, could be a crucial step in the zoo's aim to establish a self-sustaining population of the rare reptiles.
The zoo's tuatara species co-ordinator, Barbara Blanchard, said the eggs came from first-time father Tuatahi and mother Matamuri, who were introduced to each other at Christmas time.
As breeding pairs usually took five years to conceive, their success in producing eggs was "remarkable".
"The one thing that you learn about tuatara after you've been working with them as long as I have is that they tend not to do anything in a hurry, so to find eggs is an infrequent but always pleasant surprise."
Tuatara were notoriously difficult to breed, she said.
The baby tuatara would help contribute to the genetic diversity of the captive population of the reptile as neither Matamuri or Tuatahi had relatives or descendants in captivity.
The last time tuatara were successfully raised at the zoo was in the 1988 breeding season, and there were now eight tuatara living there.
Although zoo staff were unsure whether to disturb the eggs, they decided the best chance of success that they would hatch safely was to transfer them to Victoria University for incubation.
University senior technical officer Susan Keall said the eggs seemed dehydrated when they arrived, but since then had shown good signs of recovery. "The signs are that they have picked up weight and plumped out again."
In the wild, tuatara eggs are laid between October and January and can take a year to hatch. "We've got no idea when they were laid so we have no idea when they will hatch."
But it could happen at any time. Eggs kept in incubation containers often hatched in a shorter time than those in the wild, Ms Keall said.
As eggs raised in warmer temperatures produced male tuatara and those incubated at cooler temperatures produced females, four of the eggs were being kept at 23 degrees celsius and the others were at 20C.
And now I know. 