Road to recovery

Takahē numbers are rising by 10 per cent a year. The problem now is where to put them.

Written by       Photographed by Dave Hansford and Craig Mckenzie

Department of Conservation ranger Jason van de Wetering snoops on transmitter-clad takahē in the Big River catchment of the Gouland Downs. Each bird emits a signature signal, but their itinerant lifestyle—and partner-swapping culture—stifles surveillance.

This should be a doddle. We have a helicopter, GPS, and sophisticated tracking gear. From this height, the Gouland Downs in Kahurangi National Park look almost Arcadian—a gentle, pastoral ramble. Down there somewhere are 30 big blue birds, and they’re all wearing transmitters. We’re here to find them, and I don’t see how we can fail.

Department of Conservation ranger Jason van de Wetering waves a receiver through the rotor wash, listening above the din for the beep of Shadowfax. What he hears instead is the chirp of Dalrachney—the first of many baffling moments. Takahē, it turns out, are disinclined to stay where you put them. Rather, they prefer to follow some surprisingly sordid impulses: they’re down there right now, partner swapping, swinging and sexshifting.

Freed from the fence of their captive upbringing, the members of this society—the first new free-roaming mainland population of takahē in nearly 70 years—are breaking old bonds and rules, reforging themselves as they get to grips with this unfamiliar wild, and reacquainting themselves with their own evolution.

The pilot sets us gently down on what now reveals as chest-high tussock. Before the clatter of blades has even ebbed, I stumble into my first unseen bog. The takahē don’t live on the Gouland Downs, they live in them, stalking along tussock tunnels in a labyrinthine world with no horizon, and little expanse. I marvel at how they find their way.

Jason and his wife, Maddie, are waving receivers. Each bird emits a unique signal.

“Is that Mahia?”

“I think so. Who’ve you got?”

“Tīhaka.”

“I thought he was with Rusby last trip?”

Every time DOC staff check on these birds, it’s like catching up on Coro.

There are only 30 of them, but takahē have already altered the Downs. Everywhere, bushels of felled tussocks lie, as though someone has gone through with a weedeater. Each stalk is missing the bottom couple of sweet centimetres—the rest is cast aside.

Kauri, a male, creeps along a tussock tunnel at the foot of the Slate Range. Takahē construct nests in these labrynthine passages. Females lay between one and three eggs, raising just one brood a season.

The two rangers split, forming points of a pincer through tussocks bristling in a stiff sou’wester, creeping towards the source of the signal. No-one speaks: the pair use digital semaphore instead, like Marines advancing on a concealed foe. The number of fingers they hold up denotes the strength of the signal in their headphones. Jason cocks a cupped hand to his ear. Incredibly, these two can hear the jangle of the bird’s leg bands as it retreats along some hidden tunnel.

Then, Jason points two fingers to his eyes. He has the bird—Māhia—in sight. I’m regarding instead her prodigious poo. You know when you’re close to a takahē nest, because they refuse to foul it. Instead, they operate a proximal latrine, which they inundate with something a miniature horse might pass. It looks like rope. Tubular, fibrous, and frankly majesterial, a takahē’s poo is the bird’s slow-burning evolution writ large and recumbent.

The takahē diet of tussock results in an impressive quantity of fibrous poo.

There in the stools are all those short morsels missing from the clearfelled tussocks. They haven’t lost much of their substance or sustenance. Takahē run two digestive systems: they get their baseload energy, barely, by processing vast amounts of vegetation in a gut nearly 1.5 metres long but poorly equipped for extracting much more than a per diem. Trying to wring energy from cellulose is a toilsome business. Takahē in the Murchison Mountains in Fiordland can spend 19 hours a day feeding.

“They’re the pandas of the bird world,” observes Jason. “It goes in as grass, it comes out as grass.” And lots of it.

Nine metres of poo a day, as takahē cognoscenti like to quip. Consider how much a gut that long full of grass might weigh, and you start to grasp why takahē don’t fly.

However, some of those clippings get diverted into a pair of cecae, which conduct a kind of deep fermentation—the closest a takahē gets to carbo-loading. “Once or twice a day, you’ll get a black, tarry cecum poo,” say Jason, “which is low turnover, high yield,” but before I get to see one, or its maker, it rains. Oh, how it rains. The land fairly drums, yet the tussocks gleam stubbornly golden, even as a sodden sky quenches the last glowing coal of sunlight. Veterans both, Maddie and Jason produce umbrellas and get back to work. We squelch on, through knee-high heaths and ferns, dipping in and out of rivulets, threading around bogs. The first celmisias are unfurling. Over the patter of rain on Gore-Tex, a hum of white noise from the receivers.

I doubt the takahē are much inconvenienced: these high, hard places are home. The only other wild population on the mainland—around 130 birds in the Murchison Mountains—has it much harder than this: avalanches are a lethal threat there, but that doesn’t mean takahē live this high by choice.

Once, they ranged the entire South Island, right down to the beaches. We know, because their remains, part-bone, part-stone, still lie in middens everywhere. First, they were hunted by Māori. Then by European sealers and museum collectors, then by the stoats, ferrets and cats they brought with them.

There was nowhere left to go but up, although takahē can and do spend time in forest when the snows come. Some even grub for ferns there.

“From what we’ve seen, they probably used to inhabit the bush edge or mosaic habitat,” says Jason. “They’ve been seen feeding on around 14 different species of plant—they love eating European grasses; Mana Island is one of our most productive sites—and they won’t say no to the odd bit of protein either: the odd skink, a worm, or a grasshopper.”

Eggs lay in the nest of Pipper, an old female recently found dead. They are all fertile, and now being incubated by Pipper’s foster daughter, Tupuanuku. The culture of ‘helper birds’, in which offspring help parents raise their siblings, is found in as much as eight per cent of bird species.

But for the most part, it’s about turning tussocks into rope—“Maybe they’re just sticking with what they know”—and, because chicks learn how to feed by watching their parents, that’s unlikely to change anytime soon.

We dry out in staff quarters near Saxon Hut, on the Heaphy Track. When the sun resumes, we pick up the receivers and head back out, this time turning east, where beeps are coming from an exasperating maze of puggy fens, bogs and tussock tunnels against the toe of the Slate Range. Somehow, the tussocks are even higher here. But many of the takahē have gravitated to this basin, where Jason thinks the Big River and Shiner Brook may have washed precious nutrients.

It’s been eight hours, and so far I’ve seen every manifestation of takahē but the bird itself. Maddie cups her ear and points: a bird is near. Then, a curious call from the thicket, like the last few gurgles of a sink draining. And not far off, a reply. Jason pulls from his pack what looks like a small, camo-clad loudhailer and pulls the trigger, broadcasting a hoax distress call—the squeak of takahē chicks. Even I can now hear rustling, and I drop to my belly, choosing a tunnel at random. At its sunlit exit, a vast red bill appears.

I can’t understand why it took us so long to see that birds are simply surviving dinosaurs. As the takahē, Kauri, stalked into sight on those scaly legs, his eye blood-red and blinking in the sudden brightness, it was a vaguely Jurassic moment.

Takahē are probably the world’s oldest known flightless rails. Taxonomists think they arrived in proto-Aotearoa, on fully functional wings, between five and 20 million years ago, likely from South Africa, which was a much closer neighbour back then. Like so many of our birds, takahē quickly noted the total absence of terrestrial predators, and got into the habit of walking everywhere.

Kauri’s wings are just a faint digression, right about where the olive drab of what used to be his scapulars suddenly flushes into emerald flanks. For whatever similar reason—if any were needed to justify exquisiteness—his neck and breast smoulder cobalt, waiting for sunlight to set them agleam. His mantle flashes an opalescent, utterly gratuitous, Arctic blue. He looks right at me, and, prostrate in the tangle, I appreciate the ingenuity of the big scarlet rostrum that shields his eyes from the snagging brushwood.

Before I can note anything more, he melts back into the tussock subway. The fake chick caller has already told Jason what he needs to know. Takahē are protective parents, so if they have chicks nearby, they’ll call back as they come running to the fake broadcast. But Kauri saunters off. There are no chicks
here yet.

Evening is settling over the Downs. The last tatters of the front scatter the gloaming. We move on towards Shiner Brook. The headphones are back on, the receivers are waving, but before we gain the stream, Jason utters a singular, agonised cuss: “Crap.”

The transmitters fitted to these takahē contain a mercury switch that moves whenever the bird does. Should that switch go still, the transmitter waits 24 hours before changing its signal to a rapid beep—a mortality signal. Sometimes, it’s just that a transmitter has fallen off. Their harness has a deliberate weak link meant to act like a fuse. If the bird becomes entangled in brush, the link breaks and the bird continues on its now-anonymous way. Jason and Maddie hope this explains the staccato. Jason, anxious, rushes ahead, but when Maddie and I arrive, his face announces a tragedy: Pipper, a female, is dead. Now they are 29.

She’s lying, morbid and maggoty, in a pool, and she’s been there for some time. Vexingly, there are no obvious clues to her demise: no mauling from a stoat, no plucking from a falcon, no evidence of mishap. It rained hard up here last week, and maybe Pipper tried to cross the brook and was overwhelmed by the flush. Or it could just have been old age: she was at least 12 years old. “It’s always worse when it’s a mystery—you can’t learn anything from it,” says Maddie.

All the same, Jason gallantly tries to wash out the maggots before putting Pipper’s remains in a Kleensak. He and Maddie will walk out to Karamea tomorrow—two days’ tramping, carrying an extra three kilos of crumbling corpse in the hope that vets at Massey University might divine a cause of death.

The couple fear for Pipper’s nest, not 80 metres from where she died, but as we near it, their headphones ring with live signals. A remarkable thing has happened.

Like a shrouded fortune teller, Jason van de Wetering predicts the future for takahē eggs near the Enchanted Forest, on the edge of the Gouland Downs. By backlighting the eggs with a torch, van de Wetering can tell whether an egg is fertile, and how far a chick is from hatching.
After 12 years spent rebuilding her species, Pipper lies dead in Shiner Brook, her transmitter still broadcasting a mortality signal. With no obvious sign of predation, vets at Massey University will try to establish the cause of her death, hopefully offering takahē managers some vital lesson. Misadventure is a common demise for wild takahē: in the Murchison Mountains of Fiordland, they are routinely buried by avalanches.

Atop the nest, the unmistakable olive hunch of a brooding takahē. Pipper’s adopted daughter, Tupuānuku, is stoically incubating three eggs, at least one of which would have been laid by her dead mother. She’s sitting tight even as we draw near. This is how takahē have cheated extinction, and why they might just prevail here on the Downs. Their swinging, salacious society might look like pandemonium to us, but it’s a social contract—maybe 20 million years in the drafting—that champions survival in some of the toughest habitats in the country.

This nest, doomed under any strait-laced system, actually has three birds looking after it: sub-adult Tupuānuku and a pair of adults, Te Uatorikiriki, a female, and Rerehu. Threesomes are, Jason tells me, “far from unheard of”.

It wasn’t always like this: Shiner Brook used to be a respectable neighbourhood.

“I’d probably have to draw you a diagram,” says Jason, tapping his fingertips as he fact-checks his own account, “but Rerehu used to be with Lily, but he left her—she’s still by herself—and hooked up instead with Te Uatorikiriki, who was with Scoop at the time. Meanwhile, their neighbours were Pipper and Matariki, with their foster sub-adult, Tupuānuku.”

But at some point, Rerehu, homewrecker that he is, jumped the fence again and lured Pipper away from her partner. Obviously, Tupuānuku decided to go with her mother. “So Rerehu had two female partners,” continues Jason, “and Tupuānuku as a helper, even though they’re not related.”

In what may well be a revenge tryst, the two wronged parties, Lily and Matariki, have teamed up.

Maddie van de Wetering makes a hoax call, playing the sound of alarmed takahē chick to check on breeding progress. If a pair of birds come running, odds are they have real chicks somewhere nearby. Indifference means they’ve yet to raise a family.

Scoop has been especially unlucky in love. His next relationship, with Erewhon, failed too. Now, he and new partner Hyde may be hoping third time’s a charm. It’s little comfort to Hyde’s ex, Tametame, who clearly couldn’t bear the sight of his belle with a new guy and left the Enchanted Forest. The good news is, his self-imposed exile at Blue Duck Creek didn’t last long. He’s now hooked up with Temple.

“It’s quite a complex and fluid social dynamic,” Jason adds, redundantly.

There are three creamy eggs on the nest, speckled black and surprisingly different from one another. Maddie and Jason need to know if they’re all fertile: if not, they’ll remove the duds, which will prompt the birds to lay again. Jason dons a hood that blocks out the low rays of a failing dusk. It makes him look like a cross between the Elephant Man and a Klansman.

He reaches a hand out, and Maddie gently places an egg in it. Inside the hood, Jason is candling each egg, shining torchlight from behind to illuminate the embryo inside. It tells him whether the embryo is alive, and how close it is to hatching. He shrugs off the hood: within a week, if Tupuānuku holds to her task, there should be three new takahē to offset the loss of her mother.

Takahē almost forgot how to do this. For years, hatchlings at the Burwood Takahē Breeding Centre between Te Anau and Mossburn were reared by people, or more correctly, puppets. Eggs were taken off the nest and placed in incubators. On hatching, a chick was fed by a takahē-like marionette that ensured the chick imprinted on a facsimile of its own kind, rather than people.

Numbers were gained, but something crucial was lost.

“It turned out that when those birds were released into the wild, they made rubbish parents,” says Jason. “They were perfectly capable of incubating an egg, but they weren’t very good at hatching them out and raising chicks.”

[sidebar-1]

In the wild, young takahē often stay with their parents for up to two years, helping them raise the next generation—incubating eggs, as Tupuānuku is doing here, and feeding chicks. That’s a vital apprenticeship in which they learn the skills they’ll need when time comes to breed themselves.

The Burwood puppet show ended in 2011: nowadays, takahē are left to do it in their own, ancient, way. We now understand that takahē aren’t born with a survival manual in their head: they learn how to live by watching and mimicking their elders. Before they can be released into some upland site, juveniles that have never seen a tussock must be buddied up with experienced birds who can show them how to pluck, peel and peck those bottom two centimetres of stalk.

As takahē learn and evolve, so does the effort to save them.

With a gentleness like reverence, Maddie replaces the eggs. It’s so late that Sirius is gleaming above the Saxon Ridge. Weka shriek from the woods. We call it a long day.

[Chapter Break]

Derek Grzelewski wrote about takahē in this magazine 20 years ago, quoting then-recovery programme manager Dave Crouchley as saying: “For now, our aim is to breed up enough birds so that we have the problem of where to put them.”

Problem accomplished. Burwood now produces some 25 chicks a year, and a similar number are produced at 20 other sanctuary sites around the country. Crouchley did his bit—now his successors have to figure out where to put them, and that’s a thorny, if luxurious, problem. There are few safe places for takahē to go.

“Potentially, there’s a lot of nice habitat in the South Island,” says the takahē programme’s scientific adviser, Andrew Digby, “but with open areas like that come cats and ferrets, which are a real problem.”

Jason van de Wetering defies a drenching southerly near the Tubman Range to listen for the tell-tale beep of takahē. Another 10 birds are scheduled for release this summer, but the Gouland Downs is only a small, suitable island in a sea of habitat otherwise denied to takahē by cats, ferrets and stoats.

And there’s the rub: those pests are impossible to control at any sizeable scale. Takahē are only here on the Gouland Downs thanks to a vagary of topography. Cats and ferrets seem reluctant to breach a dissuasive perimeter of beech and broadleaf forest that separates the Downs from more-appealing farmland on the national park’s eastern reach.

And then there are stoats, which routinely kill a few juvenile takahē every year in the Murchison Mountains. But when the beech trees mast, losses go stratospheric: in a 2007 mast season, prodigious seedfall prompted stoats to breed to full capacity, seizing their chance to feast on the extra rats and mice nourished by the cornucopia. When the seed ran out and rodent numbers fell, hungry stoats turned on the takahē—40 per cent of the adult population was slaughtered in a single season. Trapping has since been stepped up, but undeterred by a phalanx of 3500 traps, stoats still kill up to 20 per cent of Murchison takahē in mast seasons.

Kahurangi National Park, by contrast, has had years of concerted pest control with aerial 1080.

“And that’s the main reason takahē are here,” says Digby.

“Stoats are at very low numbers here. If we could just get that landscape-scale pest control in other places, we’d have takahē everywhere in the South Island.”

But that would mean more aerial poisoning, and no-one knows yet whether takahē and 1080 can mix: “That’s the biggest question we face,” says Digby.

A complication is that birds raised at Burwood, which supplies the majority of candidates for translocation, are fed a supplement of cereal-based pellets, and while they don’t look or taste much like a 1080 bait, it means takahē from there come pre-conditioned to treat such objects as food. And they did, when DOC tested their appetite with non-toxic 1080 baits.

“We found that a lot of captive takahē—as much as 75 per cent—quite liked them,” says Digby.

But that’s unlikely to reflect the preference of a wild population, he adds, because that familiarity with cereal pellets would be lost with each wild-born generation.

“Takahē have never been exposed to 1080 before, so it’s really hard for us to tell what sort of impact it might have,” he says.

Toxicology may hold a few clues, though: takahē are heavy birds, weighing up to three kilos, which counts in their favour. The potency of the toxic agent in 1080, sodium fluoroacetate, weakens as body weight increases. Also, that low-octane grass diet means their metabolism fairly crawls—another plus, because fluoroacetate targets high-revving organs. Experience with the takahē’s smaller relative, the weka, has shown that plenty of weka eat 1080 baits, and while they appear to get sick, few actually succumb.

Just the same, says Digby, “I’d expect that some takahē might die, but we just don’t know what proportion of the population that might be.”

Jason van de Wetering applies nail varnish to a takahē egg found cracked in the nest. Young helper birds take their turn at incubating their parents’ eggs, but there’s no chromosome for care: youngsters must learn how to avoid damaging them.

Conservation in New Zealand can be a cold, calculated business. Takahē are a taonga, and there are roughly 375 left on the planet. But they can’t live in zoos forever: the whole point of the recovery programme is to bring them home, to the dunelands, the drylands, the broadleaf mosaics, the tops, of the entire South Island.

“We need more safe places for takahē, and at present, the only viable tool for controlling pests at landscape scale is 1080,” says Digby, “so we have to get to grips with this.”

There may be a solution, but for now, it’s a faint spectre on a very distant horizon. Para-aminopropiophenone—let’s just call it PAPP as everyone else does—is a meat-based, stoat-specific toxin that could solve Digby’s dilemma. But it’s still in the early stages of registration, and there remain years of exhaustive checks and balances to be satisfied before it might be approved for aerial use. PAPP, even if all goes well, will probably not be an option until the mid-2020s, and Digby has to sort this now.

“If we don’t, we might as well pack up and go home.”

[Chapter Break]

Here on the Downs, takahē are mostly their own worst enemies. Many carry wounds and scars.

“They’re very territorial,” says Jason, “and once a site starts to fill up, we see much more conflict—we’ve even had the odd bird killed in a fight.”

In suboptimal habitat, a pair of takahē might secure 60 hectares to call their own, but boundaries can shrink to as few as five hectares in lush pickings, he tells me.

“On Mana Island, where there’s lots of lush grass, they can have quite small territories. When we first looked at [the Downs], we figured there might be room here for 40 pairs, but it may turn out that there isn’t. We’ve found at other sites that if you cram too many birds in there, it’s less productive: they start fighting, and they don’t raise chicks. There’s an optimal level, and that can be hard to find, but it often works better if you only have a few pairs at a site.”

 

 

An adult feeds a well-grown chick at Burwood Bush. For years, Burwood staff fed chicks with glove puppets in their parent’s likeness, but the artifice left young birds without vital parenting skills themselves. We now understand that young takahē learn most life lessons from emulating their elders.

These Downs birds are roughly evenly split: old and young, male and female. The older birds were all proven breeders at Burwood, and chosen deliberately so that, should they fail here, the recovery team will know it’s the fault of the site, not the birds. No takahē is expendable, but these stalwarts were worth a punt, says Jason: “They have plenty of offspring in the population now, so they’re not as genetically valuable as they once were.

“We know from other translocations that it’s not usually the founding birds that ensure the success of the population—it usually comes down to their wild-born offspring. It may be that these first 30 birds struggle, but the chicks they do manage to raise are the ones that’ll carry it forward.”

The next day, I start my own long walk home along the Heaphy. To either side, windrows of plucked tussocks—evidence that anyone now has a good chance of seeing one of the world’s rarest, loveliest birds up here. I cross Blue Duck stream, where Tametame and Temple are hopefully making a go of their new love life, and wend up the benched track through the Enchanted Forest. For all I know, Hyde and Scoop may be right now choosing a nest site in here.

A takahē’s plumes belie the toughness they need to survive in some of the country’s most arduous habitat. They once lived from mountains to sea, right across Te Wāhipounamu, the South Island, but as long as introduced predators prevail, there can be no
going home.

Pasture grasses announce Gouland Downs Hut, where, to the delight of a pair of German trampers, Erewhon—still single—is grazing just metres away. After the stumbling search, the snatched glimpses, of the past two days, it’s somehow perverse to have to avoid stepping backwards onto a takahē as I fix lunch.

A party of mountain bikers pulls in, and with a glance at Erewhon, regale me with their own takahē encounters back down the track. Already, the birds are adding something wonderful to the experience of coming here. And that’s the whole point of 30 years of painstaking recovery work—that one day, we all might be tripping over takahē.