A governor's menagerie, a rescue for the weka, a kiwi population nobody quite understood, and a plan to make Kawau the largest inhabited pest-free island in New Zealand.
Why Kawau is strange
A governor's Eden
The island is named for its shags. In tradition the ancestor Toi-te-huatahi named it Te Kawau Tūmaro, the shag that stands watch, and shags still nest in the pōhutukawa that lean out over its bays. Ngāti Tai and later Te Kawerau lived here, and Ngāti Manuhiri remain kaitiaki (guardians) of the island and the neighbouring coast today.
In the 1840s it became one of New Zealand's first mining sites. In 1844–45 Kawau's copper made up about a third of Auckland's exports. In 1862 Governor Sir George Grey bought the island. He enlarged the mine manager's house into the Mansion House and spent the next 26 years and a fortune trying to turn Kawau into a private paradise.
Grey was an obsessive collector. He planted hundreds of exotic species and shipped in kangaroos, wallabies, antelope, zebras, gnu, monkeys, emus, peafowl and kookaburras. He also moved native birds around, bringing kiwi from the Hokianga. Most of the menagerie failed. The zebras never settled, and the monkeys did so well they had to be exterminated.
A few of the introductions took hold, and they still shape the island's bird life. The kookaburras and peacocks are now part of Kawau's identity. The wallabies and possums stripped the forest understorey for 150 years, and removing them is the goal of the eradication programme that began in 2025.
Tradition
Te Kawau TūmaroToi-te-huatahi names the island for its sentinel shags.
1844
Copper boomKawau's mine produces a third of Auckland's exports.
1862
Grey buys the islandThe acclimatisation experiment begins.
1860s
Kiwi and peafowl arriveKiwi from the Hokianga, a gift from Judge Maning.
1866
Kookaburras releasedGrey's birds are the only ones in New Zealand that survive.
1868
Possums releasedAlong with several wallaby species. Both go on to strip the forest understorey.
1888
Grey sells upGrey's original peafowl die out sometime in the following decades.
1976
31 weka releasedEast Cape birds found what becomes the subspecies' largest population.
1996
Weka peakAn estimated ~3,500 birds, the island's equilibrium.
2004
The peahens vanishThe remaining peacocks keep displaying anyway.
2025
Eradication begins; kiwi surveyedIn May, hunters, dogs and thermal drones go after wallabies and possums. A dog survey finds 56 kiwi and no chicks.
2026
Operations resumeAfter a summer pause, the team targets the last wallabies in Block 1.
Stories
The residents
On Kawau, endemic birds that are rare on the mainland live alongside introduced birds found almost nowhere else in New Zealand. These are the ones with the best stories.
Weka
North Island weka · Gallirallus australis greyi
EndemicFlightless railTranslocated 1976
Weka are the birds visitors notice first. They are bold, flightless and curious, and they will walk off with anything shiny or brightly coloured: car keys, sunglasses, a pink sandal. Their loud rising coo-eet calls carry across the bays at dusk.
They are here because of a rescue. By the 1970s North Island weka had nearly disappeared from the mainland. In March 1976, 31 birds from the East Cape were released on Kawau. By 1985 they had spread across the island, and by the mid-1990s they had reached an estimated equilibrium of a few thousand birds.
77–84%of all adult North Island weka lived on Kawau in the 1990s, making this small island the subspecies' stronghold
Kiwi
North Island brown kiwi · Apteryx mantelli
EndemicNocturnalBrought by Grey, 1860s
Kawau's kiwi are thought to descend from a handful of birds that Judge Frederick Maning gave Grey from the Hokianga in the 1860s. Genetic testing confirms they form a distinct, isolated cluster with very low genetic diversity, and many of the birds are closely related.
In early 2025 a kiwi-detection dog named Kimihia and her handler searched the island over three trips. Dry weather had pushed the birds off the ridges, and every kiwi was found roosting in a gully. All were adults, many in poor condition, and no chicks or juveniles were found. Researchers now think Kawau may need new birds brought in for genetic rescue, and that its own birds, carrying unique genes, could help restock the mainland.
56kiwi located in the 2025 survey, 51 handled and microchipped, zero juveniles
Kookaburra
Laughing kookaburra · Dacelo novaeguineae
Introduced 1866From Australia
Small shipments of laughing kookaburras were released in New Zealand between 1866 and 1880. Only Grey's birds on Kawau survived, and they later crossed the 1.4 km channel to the mainland. Every wild kookaburra in New Zealand descends from this one island population.
They are still scarce. The range runs along the east coast from around Whangārei south to Kaukapakapa, Riverhead and the Waitākere Ranges, centred on the Kawau–Warkworth coast. The raucous group chorus at dawn and dusk is one of the strangest sounds in the Hauraki Gulf.
<500estimated total population in New Zealand, thought to be stable
Peacock
Indian peafowl · Pavo cristatus
Introduced 1860sReintroduced 1958–89
Grey released peafowl on Kawau in the 1860s, but that population died out sometime between 1886 and 1923. The birds strutting across the Mansion House lawns today come from later releases between 1958 and 1989.
A DOC ecologist studied them from 1992 to 2010, while he was mainly there to study the weka. In winter 2004 every peahen vanished. The males kept fanning their trains at their usual display sites for five more years, with no females left to see them. Two peacocks, known locally as Solo and Two-Toes, still hold court near the house.
5 yearsof courtship display after the last peahen disappeared
Kawau — the shag
Pied shag / kāruhiruhi · Phalacrocorax varius, with black and little shags
NativeNamesake
Kawau is the Māori word for shag (cormorant), and the island is named for them. Pied shags, known locally as the "Kawau shag", nest in the big pōhutukawa at Rocky Bay and other sheltered bays.
Look for them on the rocks with their wings held out to dry. Unlike most waterbirds, shags have feathers that soak through, which helps them dive. Black and little shags also fish the harbour. Gannets plunge offshore, and flocks of white-fronted terns, which locals call "kahawai birds", show fishers where the kahawai are.
Kākā, kererū & tūī
Nestor meridionalis · Hemiphaga novaeseelandiae · Prosthemadera novaeseelandiae
EndemicForest birds
These three are Kawau's loudest forest birds. Kākā, big bush parrots, move freely between the islands of the Gulf. Kererū (wood pigeons) crash through the canopy with their heavy wingbeats. Tūī feed at flax and pōhutukawa blossom, pollinating as they go.
A council survey team in late 2025 noted a "noticeable abundance of birdlife, including kākā, tūī, kererū" at Little Vivian Bay. The forest baseline report found bird communities "relatively intact" despite the wallaby damage, which is a hopeful sign for recovery.
Kākālisted as a key beneficiary of the pest-free programme
Kororā & pāteke
Little penguin · Eudyptula minor — brown teal · Anas chlorotis
Kororā at riskPāteke endemicPāteke threatened
Kororā, the world's smallest penguin, come ashore around the rocky coastline at night. You're more likely to hear their braying calls than see them.
Pāteke, a small endemic duck once common across the country, is now New Zealand's rarest mainland waterfowl. Only about 2,000–2,500 survive in the wild, and Kawau's coastal wetlands are among the places they persist. Both species are named as priorities for the eradication project.
~2,000pāteke left in the wild nationwide (2022 estimate)
Each year, starting around September, two cuckoos fly in from the tropical Pacific. The shining cuckoo winters as far away as the Solomon Islands, and the long-tailed cuckoo spreads across Polynesia. They stay until about March.
Both lay their eggs in other birds' nests. The shining cuckoo uses the tiny grey warbler (riroriro), which lives on Kawau. The long-tailed cuckoo uses whiteheads, which don't live on the island, so the koekoeā heard here are probably just passing through. Traditionally the shining cuckoo's rising whistle marked the start of the planting season. On Kawau it arrives in the same weeks the peacocks begin to display.
"Despite the absence of females, peacocks continued to display for 5 years after all peahens were lost."Beauchamp, Notornis 60 (2013)
Working towards a pest-free Kawau
Taking back the understorey
For 150 years Grey's wallabies and possums have eaten Kawau's forest seedlings. A 2025 baseline study found the browsing had "created a recruitment bottleneck and arrested forest succession across much of Kawau Island." The eradication programme aims to reverse that.
Phase one: browsers (from May 2025). Hunters with indicator dogs and thermal drones target wallabies (Notamacropus, Petrogale and Wallabia species) and possums. Toxins are used where monitoring finds hotspots.
Summer pause, then resumption (2026). By December 2025, modelling suggested fewer than a dozen wallabies remained in Block 1, and possum eradication was well advanced. Work resumed in March 2026.
Phase two: predators (proposed). Removing rats and stoats is under discussion and depends on community agreement. A 2024 dog survey found no evidence of stoats, but the island is still vulnerable to them.
Then, recovery. Once pests are gone, species could be reintroduced from nearby pest-free islands.
Partners include Ngāti Manuhiri (through the Manuhiri Kaitiaki Charitable Trust), Auckland Council, the Department of Conservation, the Pohutukawa Trust and Island Conservation.
If it succeeds
Largest
inhabited pest-free island in New Zealand
About 100 people live on Kawau, and most of the island is private land reached only by boat. That makes it an unusually hard eradication. The expected winners are the weka, kororā, pāteke, kiwi and kākā, along with the forest that feeds them.