A baby tuatara has been found near the ranger’s house. This wasn’t just any lizard; it was the first recorded hatchling in the wild from the original founder tuatara of the island’s captive-rearing programme, or their offspring. It’s the proof that the hard work of ecological restoration is paying off and that a new generation of these ancient reptiles is successfully establishing on their ancestral home, now free of the kiore (Pacific rat). DOC staff noted a possible nest nearby last year, estimated the young tuatara’s age to be a year or less. This brings us to the core of the tuatara’s unique story: time. Tuatara egg shells from Te Hauturu-o-Toi’s captive rearing programme. Photo by Shaun Lee. The Tuatara Life Cycle: A Study in Slowness The tuatara’s claim to fame as a ‘living fossil’ comes with a famously slow pace of life, making their reproduction a particularly vulnerable process. Laying Eggs: A female tuatara in the wild will typically lay a clutch of 11 eggs only once every four years. Incubation: Unlike most reptiles that hatch in a few months, tuatara eggs are buried and take an extraordinary 11 to 16 months to hatch. That’s a huge window of time for predators to find them, which is precisely why the kiore posed such a devastating threat. Maturity: Tuatara take an incredible 13 years to reach sexual maturity. Lifespan: They live a long time – typically 60 years but some experts believe that captive tuatara could live as long as 200 years! The discovery of the hatchling on Te Hauturu-o-Toi is a monumental success because it confirms that the entire, long process—from mating and nesting to a year of incubation and a successful break from the egg—is now naturally occurring without the threat of introduced predators. Climate change is a threat to reproduction Despite the conservation successes like the one on Te Hauturu-o-Toi, a massive, global threat looms over the tuatara: climate change. Tuatara, like many turtles and crocodiles, exhibit temperature-tependent sex determination. This means cooler nest temperatures produce females, while warmer produces males. As global temperatures rise, conservationists fear that nest temperatures will skew heavily towards producing males, leading to a shortage of breeding females. If the sex ratio becomes too imbalanced, the population will no longer be able to sustain itself. To combat this, active conservation efforts may eventually need to include managing nest temperatures or relocating eggs to cooler islands or artificial incubators to ensure a healthy ratio of female hatchlings.
