They were on the hunt for a species declared extinct half a century before. Spurred on by determination, and belief that previously unidentified signs — strange bird calls and footprints in the tussock — could only belong to one particular bird, the expedition came to what is now known as Lake Orbell. There, standing half a metre high, bright iridescent blue and green and eyeing them with indifference was Notornis.
The programme has seen many phases, from intensive hand rearing, to establishing populations on a number of mainland and island sanctuaries to the now well-oiled machine of parent birds raising chicks per year. This has meant the team are now in the position to push the envelope and establish a second wild population in Kahurangi National Park. All the surveying and research was done on foot, and the inquisitive birds would come and investigate the visitors, then graze quietly nearby, feeding chicks just a few metres away, unbothered, undisturbed.
But they learnt quickly. They fled as if the earth were on fire. Morris recalled how he once found an almost fully grown chick submerged in a mountain stream, waiting for the intruder to leave.
Today, even such unorthodox evasion tactics would not work. In many of the families there is a bird which carries a miniature radio transmitter. They can run, but they cannot hide.
A helicopter-mounted receiver can find them with pinpoint accuracy. I had already seen this bird sleuthing in operation, and its intrusiveness had left me feeling ambivalent about this research. But for science, locating them was not enough.
As the helicopter herded the takahe uphill—the rotor blades almost weed-whacking the tips of cliff-side bushes—the researchers strained their eyes to record the colour codes and dutifully tick them off on their clipboards. Is it black?
Scientists are surely dedicated to their work, I thought, watching from the back seat, but what did takahe—acutely aware of aerial predators such as falcons and black-backed gulls—make of this red-and-white monster chasing them up bluffs, roaring like an avalanche and blowing a hurricane?
Had the mission to save the birds become more important than the birds themselves? Was this type of research really necessary? There is no other practical way of finding out. Which would you choose? Maxwell is a bush-wise young biologist with many voluntary stints on other endangered species to her credit. She spends up to four weeks at a time in the Murchisons, tracking the birds on foot.
In her spare time she kayaks the Fiordland coast. In winter. But back in the chopper I knew none of that, and so I continued to ruminate on the narcissistic nature of science. And so we did. Bird after bird, cirque after cirque, valley after valley, ad nauseam.
Containers for lost pride. The morning after the storm dawned clear and cold, revealing a fairytale landscape muffled by fresh snow. Other birds appear much more at home. From the air I had seen the purposeful beeline tracks of a brown kiwi, cutting across steep snowfields and following exposed ridges, its claws doubling for crampons, its beak stabbing the snow like an ice-axe.
These mountain clowns are truly at ease here, taking time out from the business of survival to frolic in the snow, rolling about like a pair of puppies, or to examine the colourful gear of human visitors with a systematic curiosity that, given different circumstances, could pass for scientific zeal. Takahe do none of that. Examine a segment of this cable and you will understand why the birds generate so much excreta.
The problem is, there is little nourishment in even the juiciest of these tough mountain grasses. And so, driven by insatiable hunger, the birds feed as if there were no tomorrow. Not only is their main food of poor nutritional quality, but takahe have had to compete for it with much larger and more mobile browsers. The introduced red deer has stripped large swathes of Fiordland of its native vegetation.
In the s, red deer started spreading across the land like bushfire, with a similar impact on the forest and alpine flora.
Fortunately for the plants, the price paid for venison was good, and so the infestation soon turned into a kind of game-meat gold rush.
Then, with the advent of helicopters and deer farming, attention turned to live capture, with men leaping out of choppers to bulldog fully grown hinds to the ground—a job so inherently dangerous that the life expectancy of a deer wrestler was estimated at about three years. By the mids, the deer population was finally brought under control.
But for takahe it was almost too late. Tussock is slow to recover from heavy browsing—up to 20 years, suggests a recent study—and without food the takahe population began to collapse. By the early s, there were just over takahe left. There can be little doubt that without the major conservation effort that followed there would not be a wild takahe in Fiordland today.
The valleys were topdressed to speed up the recovery of the tussock, and eggs were shuffled between nests to ensure that each pair would bring up a chick, but both actions had little tangible effect. On the inside, the unit resembles a small maternity ward, though you wear sterilised white gumboots instead of slippers. The chicks almost never see the puppeteers. At about two weeks of age, all the chicks are brought into the brooding unit to be reared by the puppets. When they are seven to nine weeks old, they are switched to pelleted food and moved outside to an hectare enclosure which looks like a free-range poultry farm with an electric fence and a mustelid trapline around its perimeter.
Crucial to future survival are lessons on digging up fern rhizomes, a winter staple of which the novitiates seem to have no innate knowledge. Sometime in October, almost a year after the eggs are collected, the juveniles are released back into the wild—back to stringy tussocks and cold winters. From then on their life will be a continuous test of survival. It is a test that, thanks to the remarkable efforts of the Burwood Bush personnel, the young takahe have latterly been managing to pass rather successfully.
Their survival rate—up to 60 per cent—matches that of birds raised in the wild, though it depends on where they are released. In the mids, the number of Murchison birds was on the increase, and wildlife managers thought it prudent to found another population. They looked long and hard, and in the end decided on the Stuart Mountains—similar in topography, just north and across the Middle Fiord from the Murchisons.
Between and , 58 captive-reared takahe were released into the Stuarts. Almost all of them vanished. The Stuart site was abandoned, and since takahe have been released into the Murchisons again. By the end of , the number of new arrivals will have totalled 86 birds—enough to give a tremendous boost to the population were it not for a string of unusually heavy winters in the early s. The winters here can indeed be fierce.
The gorge leading to Lake Orbell sprouts tree-trunk icicles along its walls, the lake itself freezes solid and DoC staff wear heavily insulated Antarctic surplus boots. Despite almost two decades of intensive efforts, despite eggs and chicks shuttled by helicopters, despite weeks and months spent in the field by dedicated and enthusiastic DoC staff, the last summer headcount revealed just birds.
Just how, in an evolutionary sense, did the takahe find itself in such strife? It flies with a contorted jerky motion, but only for a short distance, alighting on any tree handy, and staggering among the branches as if intoxicated. It walks as if troubled with corns, and in running it often stumbles.
When swimming it looks like a domestic fowl tumbled in a water butt and wanted some kind friend to rescue it. Its diving is still more absurd. Despite its ungainly predisposition, the pukeko proved to be a most successful coloniser.
In some parts of Otago and Southland they were becoming a nuisance and a price was put on their heads. At first glance, the difference between the two birds is obvious: pukeko can fly, takahe cannot.
Pukeko are omnivores, takahe, except for the first two weeks, when the chicks are fed insects, are predominantly herbivores though this may be more out of necessity than choice. Pukeko can live in large groups with the intricate hierarchy of a wolf pack, build communal nests which can contain up to 25 eggs, and mob a predatory intruder when threatened.
He was a keen tramper and hunter and had an inkling that there might be some birds surviving somewhere in Fiordland. They were armed with a net to catch the giant flightless birds, and cameras to record the momentous occasion.
The news of the discovery travelled quickly around the world. Telegrams flooded in from news organisations around the world, and the team were much in demand for interviews. A pair of young takahe are released in Fiordland by descendants of the party that rediscovered takahe in Joan Watson, the last surviving member of that original team, died recently.
Joan Watson on the shore of what would become known as Lake Orbell, with one of the rediscovered takahe, in November They made their way down to an un-named lake, where they shot a deer. This time the party included Joan. It was a very difficult climb. It took about three hours.
So we were all crouching and peering, and through the snow grass I caught a glimpse of the bright red beak.
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