This Is How It Ends: Small, secretive, and increasingly rare — why reptiles need our help

Thursday, 21 October 2021

How tiny bats, snails and frogs are sending signals about the death of the planet.

Stuff’s This Is How It Ends series features the Archey’s frog, one of the world's rarest and most endangered amphibians, cared for at Auckland Zoo. The zoo’s head of animal care and conservation Richard Gibson explains why we should also be worried about New Zealand’s elusive reptiles.

OPINION: Aotearoa, known to many as the land of birds, is very much a land of lizards. There are more endemic lizards here than terrestrial birds.

But they are small, secretive, and increasingly rare. At least half are considered threatened and three-quarters declining in range and numbers.

There are six groups of reptiles. New Zealand has no Amphisbaenia or Crocodylia, and the tuatara is the sole survivor of Rhynchocephalia.

Of Testudines, five marine turtle species are considered native: the green, loggerhead, olive Ridley, hawksbill and leatherback turtles.

Then, Serpentes. Sadly, just a handful of snakes, all marine, are considered native. The strikingly beautiful yellow-bellied sea snake drifts with ocean currents but washes up frequently on our shores.

The other ‘native’ snakes are three species of banded sea krait. These are the sea snakes you’ll see on a stroll along a Pacific tropical-island beach, particularly in Niue.

A tuatara, sole survivor of the reptile class rhynchocephalia.

And so to the piece de resistance: Sauria, the lizards.

In the last couple of years, at least nine new species were formally described. And there are plenty more waiting in the wings for a taxonomist to find the time to write the description.

Auckland Zoo has a connection to five of these new species.

A ‘safety-net’ population of Oligosoma salmo (the Kapitia skink) was brought to the zoo in 2018 for safe-keeping.

Richard Gibson, Head of Animal Care and Conservation at Auckland Zoo

Their habitat is affected by high tides, heavy rains and cyclones, but the skinks are doing OK. There are perhaps as many as 1000 in the wild, still very rare.

The Department of Conservation secured a patch of land and installed a predator-proof fence. Rodent eradication is currently underway, and before too long the ‘safety-net’ population, now grown to 65, will take up residence in the new reserve.

O.albornense, the Alborn skink, is currently one of the very rarest with only 47 individuals ever recorded.

The northern striped gecko is considered 'threatened – nationally vulnerable'.

O.hoparatea, the white-bellied skink, was virtually unknown until Auckland Zoo’s Conservation Fund supported a series of surveys. DOC considers this to be one of New Zealand’s most threatened lizards, and it is not clear how to save them in their remote, extreme environment.

Toropuku inexpectatus, the northern striped gecko, is one of my personal favourites.

Working with Mahakirau Forest Estate, the zoo has recorded around a hundred individuals, and are about to embark on a new phase of research with Massey University to radio-track some individuals.

Cobble skink was first discovered in 2007, and only known from a tiny beach north of Westport.

The yet-to-be described cobble skink was famously extirpated from the wild West Coast beach at Granity by Cyclone Gita and survives only at Auckland Zoo, or so we think.

The cobbles have gone great-guns at the Zoo, despite being a tricky species to manage with their intersexual aggression and tiny, fragile babies (imagine a matchstick with legs). We have grown the rescued population from 37 to more than 70.

Plans are afoot to start moving some skinks to a DOC facility on the West Coast.

But many species have been overlooked by conservation. We know very little about most species and even less about how to conserve them.

We have among the most innovative pest-control tools in the world.

However, these are focussed on just a few of the worst mammal offenders and protocols for their deployment are largely based on recovering birds.

We’re only just starting to research the different impacts of all these predators on lizards, to consider how much you need to suppress each for lizards to recover and what happens when you remove only some of the predator species in a habitat?

So, the next time you are in the garden, think about making it more friendly to lizards; the next time you go for a walk, think about the lizards that you might be walking by.

And the next time you visit Auckland Zoo and walk through Te Wao Nui, stop and admire the lizards and spare a thought for the dozens of threatened relatives fighting for survival across Aotearoa.

Lizards need all the friends they can get.