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Itook one big leap and let out a sigh of relief when my feet hit
solid ground. I dropped my bag and turned around to help

unload supplies as they were tossed off the boat that had just
brought us from the little village of French Pass, New Zealand.
Stephens Island lacks a proper wharf, just a bit of rock that sticks
out into the ocean, so landings can be quite a challenge when
the sea is rough. From our landing site, we carried our gear up
a narrow track and put it in a trailer that would be winched up
the hill. All of the gear would be placed in the rat-free room until
we could check it for rodents trying to hitch a ride to this pred-
ator-free island. Not counting marine life, the only native mam-
mals found in New Zealand are two species of bats, but numer-
ous other mammalian species that have been introduced either
purposefully or inadvertently have wrought havoc on this island
nation’s wildlife. For many endemic species, predator-free islands
such as Stephens are one of the last safe refuges.

Every ecosystem seems to have its own battle with invasive
species. In the States, Honeysuckle, Kudzu, Zebra Mussels, and
pretty much everything in south Florida has taken advantage of
hospitable conditions and the absence of predators and com-
petitors, but nowhere are ecosystems more vulnerable to the
effects of invasives than on islands. Perhaps that is why the fauna
of island nations such as New Zealand have been so devastated
by the introduction of nonnative species.

Because Stephens is a scientific reserve administered by the
New Zealand Department of Conservation (DoC), access is
restricted to researchers and DoC personnel in order to protect
the island’s unique wildlife. After a hike up the steep hill to the
hut, we certainly got the impression that the conservation meas-
ures were working. With every few steps, we noticed a rustle in

the grass or a glimpse of a tail just as it was disappearing. The
place can almost be considered a temperate version of the
Galápagos, with Fairy Prions (Pachyptila turtur) instead of
Boobies and Tuataras (Sphenodon punctatus) instead of Marine
Iguanas. Wildlife is everywhere, and much of it is endemic to
New Zealand. Sea Lions rule the beaches and sea birds such as
“titi” (Sooty Shearwaters, Puffinus griseus) and Fairy Prions fly in
from the ocean at night. Three kinds of “weta” (giant nocturnal
cricket-like insects in the family Stenopelmatidae) inhabit the
forest and little Blue Penguins (Eudyptula minor) hop up the hill
every evening after they return from the sea. The summit of the
island holds a rock bank that is home to Hamilton’s Frog
(Leiopelma hamiltoni), perhaps one of the most endangered frogs
in the world. Despite all of these marvelous creatures, however,
Stephens Island is truly an island of reptiles. With four species
of skinks, three types of geckos, and the largest colony of Tuataras
in the world, the entire island seems to be ruled by “lizards.”

Stephens Island has no shortage of researchers. I was there
for a week to help one of them, Jo Hoare, set up a radio-track-
ing project to study the behavior of Marlborough Green Geckos
(Naultinus manukanus). As I walked up the steep trail that zig-
zagged its way up the hill, Jo pointed out a few of the island’s
landmarks — the trail that led down to Queen’s Beach, the
winch house which was spewing smoke as the ancient piece of
machinery groaned and pulled our gear up the slope, the old
sheep-shearing barn converted into a lab known as the Palace.
All the while, though, I was staring at the ground, trying to
catch a glimpse of what was rustling in the clumps of tussock
along the path. We stopped for a moment to catch our breath
(nothing on Stephens is flat and the trails are often narrow and

38 IGUANA  •  VOLUME 12, NUMBER 1  •  MARCH 2005 GERMANO

T R A V E L O G U E

Stephens Island from the air. Photograph by Jo Hoare.

Stephens Island: Land of “Lizards”
Jennifer Germano

Zoology Department, University of Otago, Dunedin, New Zealand

Location of Stephens Island, New Zealand. Graphic by John Binns.



IGUANA  •  VOLUME 12, NUMBER 1  •  MARCH 2005 39STEPHENS ISLAND

filled with holes from the Tuatara and Fairy Prion burrows) and
Jo motioned for me to go ahead. That was when I spotted my
first Tuatara, sitting in the middle of the path with its crest
proudly erected. It stared at me for a moment and only when I
approached very closely did it scuttle into the safety of the grass.
Amazed, I walked on and smiled as I saw another Tuatara bask-
ing only a few meters farther along the track. With up to 2,000
Tuataras (or “tuts” as they’re commonly called) per hectare,
Stephens Island is truly a herpetologist’s paradise. 

Due to its split from Gondwanaland some 80 million years
ago and the fact that humans arrived only during the last 1,000
years, no mammalian predators are present, and New Zealand
consequently has one of the most unique herpetofaunas in the
world. A number of New Zealand’s species have been called “liv-
ing fossils,” species that have changed little from their extraor-
dinarily ancient origins. These include the Tuatara and all four
of the native leiopelmatid frogs, the most endangered of which
lives on Stephens Island. In addition to these ancient species, the
lizards have their own unique adaptations, including a number
of skinks and geckos that are livebearers.

Within an hour after disembarking from the boat, I was
climbing trees with a radio receiver in hand trying to find the

first of Jo’s telemetered geckos. Marlborough Green Geckos have
reached such a level of camouflage that they are almost unde-
tectable on the leaves of the native bushes. Their color, in addi-
tion to the fact that they move very little — and very slowly
when they do creep from leaf to leaf, makes them perfectly
adapted to a world in which the main threat comes from avian
predators. Jo, a Ph.D. student at Victoria University, is studying
these geckos in the presence and absence of introduced preda-
tors to see if the threat of mammals such as stoats, ferrets, and
rats has affected their basking behavior. After locating the first
gecko basking happily on top of a tree, we decided that the
transmitter attachment wasn’t having any ill effects on the
gecko’s movements. This meant that Jo could proceed with her
project and we set off to catch four more geckos. This was eas-
ier said than done, as it took nearly an hour with five people
searching to locate the next two geckos that would be tracked
for the study. 

We attached transmitters to the geckos using a sort of back-
pack made of colored gauze and bandage tape with the trans-
mitter’s antennae trailing along the back and tail of the lizard.
We released the lizards where they were caught and monitored
their movements among the trees every hour for the next week.

Fairy Prions (Pachyptila turtur) are one of many species of sea birds
found on Stephens Island. They often nest in burrows not far from
the Tuataras that have been known to eat their chicks. Photograph by
Jo Hoare.

A Common Skink (Oligosoma nigriplantare) pauses before escaping
into the grass. Photograph by Jo Hoare.

A “weta,” this giant cricket-like creature is one of New Zealand’s
largest insects. Photograph by Phil Bishop.

A Tuatara (Sphenodon punctatus) outside its burrow. Although prima-
rily active at night, Tuataras occasionally may be seen during the day.
Unlike most of the lizards that they superficially resemble, they toler-
ate very cool temperatures. Photograph by the author.



The fact that these geckos move very little, if at all, made our job
a bit easier, and gave me plenty of time for spotting skinks and
Tuataras along the trails. 

Most of my days on Stephens consisted of tracking Green
Geckos, which went fairly smoothly until we decided to attempt
tracking one of the nocturnal Common Geckos (Hoplodactylus
maculatus). While the Green Geckos spend most of their time
on leaves and tree branches, making them perfect candidates for
the use of external transmitters, the Common Geckos tend to
wedge themselves under rocks, in crevices, or between boards —
and this one was no exception to the rule. A day after releasing
him, he ended up with nearly fifty other geckos in between the
boards that held up the roof of the old woodshed behind the for-
mer lighthouse keeper’s home. Staring into the eyes of a dozen
geckos peering at you from under the sheetmetal roof made it

rather clear that observing only one gecko was going to be quite
difficult. It also meant that the possibility of the transmitter get-
ting jammed or coming off was anything but remote. Jo ended
up abandoning this portion of her project after I left, focusing
solely on Green Geckos. 

Each night, as we were finishing dinner in the old light-
house keeper’s home that now serves as a field base for
researchers, scientists studying the nocturnal critters of the island
donned their headlamps and headed out into the dark. Feeling
fairly awake, I decided to join some of them and set off to the
island’s highest point to help with the Hamilton’s Frog census.
As I mentioned earlier, Hamilton’s Frog is New Zealand’s most
endangered frog, with only 200–300 individuals occupying a
600-square meter rock pile on Stephens. The trail to the top of
the island is narrow and winding and bordered on either side by

40 IGUANA  •  VOLUME 12, NUMBER 1  •  MARCH 2005 GERMANO

A young Marlborough Green Gecko (Naultinus manukanus) basking
on a leaf. Photograph by the author.

An adult Marlborough Green Gecko (Naultinus manukanus) with a
radio-transmitter backpack. Photograph by the author.

A Tuatara (Sphenodon punctatus) perched above the trail at night. Photograph by Jo Hoare.



IGUANA  •  VOLUME 12, NUMBER 1  •  MARCH 2005 41STEPHENS ISLAND

trees and bushes and the occasional stinging nettle.
Unfortunately for me, it had started raining during dinner —
great for frogs, not so good for dirt tracks. Halfway up the steep
hill, with the Fairy Prions attracted by our headlamps and fly-
ing into our heads, I managed to slip and fall into a patch of net-
tles. Now, this stuff is unlike anything I’ve ever encountered in
the States. No itchy red rash like Poison Ivy, no visible thorns or
prickles to remove — but the minute you touch it, you know.
My whole hand swelled up and I felt a burning sensation run
through my fingers. The good thing about working with biolo-
gists is that they have a pretty good understanding of their envi-
ronment, and within a few minutes someone had found a local
plant, whose leaves we crushed and rubbed all over my hand to
numb the pain. It wasn’t entirely adequate and the strange tin-
gling feeling in my hand persisted for nearly a week, but it was
bearable.

After the nettle incident, I managed to make it up to the
frog bank. A series of boardwalks have been constructed to criss-
cross the giant rock pile where the frogs live, allowing researchers
to monitor the population without the danger of squashing
frogs. In addition, a giant fence has been constructed around the
rock pile to keep the Tuataras out. Crazy to think, but this is one
of the few places where one rare species must be protected from
being eaten by another. We did find one young tut that had
managed to sneak in among the rocks, no doubt a bit fuller from
a feast of frogs. He was caught and placed in a bag so he could
be relocated outside the frog bank. 

We moved slowly along the boardwalks, crawling on our
hands and knees trying to catch a glimpse of the frogs. Unlike
most frogs, the native species of New Zealand don’t call. One of
the most primitive frogs in the world, they lack eardrums and
can’t hear. Researchers believe that they communicate more like
salamanders than other anurans, using some form of chemical
communication to differentiate between kin and non-kin, male
and female, and the size of other individuals. In addition, these
evolutionarily peculiar frogs breed without water and, although
it has yet to be confirmed in the wild, males in captivity tend to
the young by guarding the eggs and later carrying the little
froglets on their backs. We managed to catch nearly a dozen of
these frogs, all of which were put into plastic containers until

they could be weighed, measured, and photographed before
being released at the original site of capture.

After a long night of frogging, we made the hike back down
the hill to the hut. The fog had rolled in from the sea, but you
could still see swarms of seabirds flying through the headlamps’
glare. They were so close that you could smell them and feel
their wings beat as they flew past. Others made it a bit closer
than that and occasionally you would look up just in time to see
a Fairy Prion fly right into your face before crashing onto the
ground, where it would wobble around, searching for its bur-
row.

After a few nights of frogging and one full night of sleep
(although sleep is hard to come by in a hut that is constantly
being bombarded by seabirds…… earplugs would be highly rec-
ommended to any future travelers to Stephens), I decided that
the time had come for a night out with the Tuatara team. Led
by Nicola Nelson of Victoria University in Wellington, the tut
team spends months every year monitoring the breeding popu-
lation of Tuataras on Stephens Island. Armed with PIT-tags,
flashlights, and some pretty heavy-duty Pesola scales (although
you must remember that this is coming from someone who

A nocturnal Common Gecko (Hoplodactylus maculatus) searches for
prey in the dark. Photograph by the author.

The lighthouse on Stephens Island guides boats through the Cook
Strait. Mount Taranaki on the North Island is visible in the back-
ground. Photograph by Phil Bishop.

A Hamilton’s Frog (Leiopelma hamiltoni) emerging from the rock piles
at night. Photograph by  the author.



works with skinks and frogs that you can easily hold in one
hand), we split into groups and moved into the fields that were
until recently grazed by sheep. DoC removed all of the remain-
ing sheep from the island within the last year, although the
female Tuataras seemed to prefer the unnatural short grassy fields
to the forests. Despite this, they still tend to move out from the
bush each night to dig their nests in the dirt of the old paddocks. 

Surprisingly, Tuataras aren’t that hard to catch. Just like a
snake, you grab them right behind the head in hopes that they
won’t turn around and bite you with their three rows of teeth

(one on the lower jaw and two on the top, a feature that distin-
guishes Tuataras from iguanas and other lizards). Once you have
them in hand, they generally remain calm and tolerate being
weighed and tagged without too much of a fuss. We spent the
rest of the night walking transects through the fields and catch-
ing any females we encountered. Nests were marked with a bit
of flagging tape and the females were checked for PIT-tags to see
if they had been marked during a previous nesting year.

To observe these amazing creatures in their natural habitat
was truly an opportunity of a lifetime. The tuts are the only liv-
ing members of the Order Sphenodontia and, although they
were once found throughout New Zealand, today they are lim-
ited to a handful of offshore islands. Unfortunately, perhaps
because their eggs are laid in burrows on the ground, the main-
land populations of these animals disappeared after the intro-
duction of predators such as rats. Unlike lizards, Tuataras don’t
have visible ear openings and the young tuts have a “third eye”
to collect extra UV-rays during the first few months of their
lives. In addition, male Tuataras lack a penis, mating by passing
sperm directly from cloaca to cloaca. 

Tuts remain active through most of the night, preparing
their nests, mating, and feeding on wetas and the unsuspecting
chicks of seabirds that dig their burrows nearby. It takes nearly
the whole night to finish the transects before heading back to
the hut. Only a few hours of sleep for me and then I’m up early
to pack my things. A helicopter brings supplies to the island
once a week during the research season, and this is to be my ride
back to the mainland. Unfortunately, due to the unpredictable
New Zealand weather and a bit of persistent fog, three attempts
were necessary before the helicopter made it to the island.

We lifted off from the grassy lawn next to the lighthouse
and moved out over the ocean. I watched as Stephens Island dis-
appeared in the fog behind me. A week is not enough time to
spend in such an amazing place. Few people ever get a chance
to see some of the exceptional creatures that live on the offshore
islands of New Zealand. With visitors restricted to researchers
and DoC staff, fewer still have the opportunity to visit Stephens.
However, perhaps because of those restrictions, life goes on for
the reptiles of Stephens Island — and I’ll certainly never forget
my little glimpse into their world. 

42 IGUANA  •  VOLUME 12, NUMBER 1  •  MARCH 2005 GERMANO

The author successful in her search for nesting Tuataras (Sphenodon
punctatus). Photographer unknown.

A Tuatara (Sphenodon punctatus) making a meal of a “weta.”
Photograph by Phil Bishop.

A Tuatara (Sphenodon punctatus) in front of Stinging Nettle (also
known as “ongaonga” in New Zealand). Photograph by Jo Hoare.




