Captured on camera – the first ever image of tuatara mating in the wild on mainland New Zealand, at Wellington’s Karori Sanctuary Photo by Tom Lynch

It takes tua to tango

For the first time in over 200 years, our iconic ‘living dinosaur’, the tuatara, is showing signs of breeding in the wild on mainland New Zealand.

Less than 18 months ago, tuatara were extinct in the wild on mainland New Zealand. However, in December 2005 an arrangement between Ngati Koata and Wellington’s award-winning Karori Sanctuary saw 70 Cook Strait tuatara (Sphenodon punctatus) transferred from Stephens Island (Takapourewa) to the 225ha wildlife sanctuary in the capital.

“The aims of the transfer were to test the viability of restoring this iconic species to the mainland and, if successful, establish a new breeding population” says Sanctuary conservation scientist Raewyn Empson.

“The fact that the tuatara are beginning to show breeding activity is an encouraging sign that they have settled into their new home. Although tuatara have bred successfully in captivity, this is the fist time they have mated in their natural environment on the mainland for at least 200 years, so we are all very excited.”

So far, only one pair has actually been observed mating, but there are several other potential couples in the Sanctuary. Tuatara are most active at night, and this couple have been observed mating by visitors on several of our night tours as well as during the day. But because mating occurs irregularly, occurring several times a day, or once every couple of weeks, and usually lasting less than an hour, it was extremely lucky to capture this image on camera in broad daylight.

Additional information on tuatara breeding behaviour

• Tuatara breed only every two to four years.
• Unlike lizards, the male tuatara does not have a penis. He mounts the female and passes sperm straight from his cloaca to hers (the cloaca is a small opening that serves the intestinal, urinary and genital tracts of certain reptiles and birds).
• Female tuatara become fertile at about 13 years age.
• She will carry up to 12 eggs for nine months.
• The leathery eggs will be laid between October and December; buried and abandoned.
• After about 12-15 months the eggs hatch, the young using an egg tooth to break out of their shells. From day one, tuatara take care of themselves.
• Like alligators, crocodiles and turtles, a tuatara’s gender is determined by the temperature at which it was incubated in the egg. Eggs laid in warm soil hatch into males, those in cool soil hatch into females, and those in moderate or oscillating temperatures into a mix of both.
• Tuatara are born with a legendary ‘third eye’ (actually a light-sensitive pineal gland) on the top of their skulls. This slowly closes over as they mature.