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New Zealand's bizarre un-bird - kiwi
International Wildlife,  May-June, 1997  by Tui De Roy

Once it was regarded as a scientific hoax--now it's merely an "honorary mam- mal"

On a windless night with no moon, I wait patiently in a mossy recess of one of the wildest places I have ever known--the primal forest of New Zealand. The silence is deafening, the darkness total. My senses are so acutely sharpened I can hear my own heartbeat.
Suddenly, an electrifying shriek tears apart the stillness: Like a steel blade stabbing the night air, a territorial call rips from the forested ridge just beyond me. Half scream, half whistle, repeated over and over again, the stri- dent notes rise with intense conviction--questioning, asserting, proclaiming. "Cruuuik, cruuuik, cruuuik!"

I hold my breath, feeling the hairs stand up on the back of my neck. Within seconds, an answering volley erupts no more than 15 meters (50 ft.) away from me in the inky darkness. These calls are equally forceful but infinitely har- sher, a combination growl and scream sounding remotely like the creaking of a very old, very rusty, very loud barn door.
Just as abruptly, silence returns to this forest that has remained virtually unchanged for 70 million years, and I am left to marvel at my good luck. I am at last in the company of one of the world's most bizarre, most secretive and most well-loved birds, and I have just witnessed a female respond to her lifelong mate. My quarry is the New Zealand kiwi, arguably the most un-birdlike bird that ever existed.
So strange is the kiwi that it was once regarded as a scientific hoax. More recently, it has been termed an "honorary mammal." For a start, the kiwi is completely tailless and flightless, not even able to flap the stubs of remnant wings for balance. Long, catlike whiskers accompany shaggy, hairlike feathers. Sturdy, muscular legs--a third of the bird's body weight--enable it to lope through the forest. Like some rodents, it is nocturnal. Like a badger, it lives in burrows.

Most amazing of all are the bird's senses. The kiwi has traded the keenness of avian eyesight for acute non-avian senses like hearing and smell. Its ears are so well developed they can be seen easily through furlike head feathers. And its sensitive "nose" can sniff out food as acutely as can any dog.

The kiwi's extraordinary beak--which is incredibly long and thin and, in con- trast to all other birds, has nostrils near the very tip--is a combination scent detector, probe and forceps. A kiwi can thrust this 18-centimeter-long (7 in.) device completely underground to sniff out earthworms, its favorite food. Or it may lift it into the air to detect smells wafting on the wind. This unorthodox tool allows the kiwi to snuffle along the forest floor like a hedgehog and probe the ground for invertebrates like an anteater.

Equally unusual is the way kiwis breed. The female is up to 30 percent heavier than her mate and produces one of the largest eggs in relation to body size of any bird, up to 20 percent of her own weight. A chicken of the same size lays eggs less than one-sixth as large as the kiwi's. This giant kiwi egg consists of nearly two-thirds yolk, an incredible energy investment.

Not surprisingly a wild female kiwi lays only one or two eggs a clutch, which she may leave entirely to her mate for an incredible 70--to 80-day incubation. When a chick finally hatches, it is already fully feathered and resembles a miniature chip off the parental block. At the age of two weeks, it will wander off into the forest alone, a fully autonomous mini-kiwi.

All these thoughts flood my mind as tonight I try to imagine this pair on independent foot patrols of a shared territory, which in some cases may be as large as 40 hectares (100 acres). Where did kiwis come from and how did they come by such a mammalian lifestyle?

The story, I realize, goes back some 70 or 80 million years to the time of the break-up of the super-continent Gondwana, when what was to become New Zealand first split away from the rest of the world's land masses. At that time, mam- mals were still an evolutionary minority, and birds reigned. On an island which to this day has never known native land mammals except bats, it would be only natural that a bird like the kiwi would come to be.

Kiwis appear to be distantly related to the rest of the flightless ratite fam- ily, like ostriches in Africa and emus and cassowaries in Australia and New Guinea, although they are by far the smallest of the tribe. There are actually as many as six different forms of the bird, divided into four main types: the brown kiwi, the tokoeka, the great spotted kiwi and the little spotted kiwi. These range in size from a small bantam hen to a Rhode Island Red, two-and a half times bigger.

The hours pass quickly and silently on my night watch in the woods. Far in the distance, another kiwi calls faintly from across the valley. Suddenly, foot- steps crackle and crunch through the leaf litter, heavy and firm and approach- ing fast. I flick on my pocket flashlight. And there she is in all her aber- rant glory, a female great spotted kiwi as large as they come, standing all of 40 centimeters tall (16 in.), beak tucked straight down and razor sharp claws ready to lash out.

I know kiwis are extremely protective of their turf, especially males that may fight each other to death, so I'm hoping she'll edge closer to investigate, giving me a better view. I can see her fine, speckled, mousy "fur," her need- lelike, flesh-colored bill and her massive legs and feet planted squarely, wide apart. Then in a flash, she ducks behind a tree and vanishes. Her heavy footfalls and loud, snorting sniffs tell me that for a good ten minutes she is still checking me out, but try as I may, I cannot lure her from the undergrowth. At last she vanishes like a ghost into the night.

Despite this secretive nature, the kiwi has long captured the spirit of New Zealanders. The native Maori people, whose ancestors arrived from other Pacific islands some 1,000 years ago, still revere the kiwi as a creature of legend, one that, according to tradition, protected them and provided them with food. To the Maori, the kiwi is an older brother, the child of Tane, god of the forest, who fathered much of the natural world, including birds, trees and humans.

The kiwi equally found a place in the heart of the hardy white pioneers who later colonized its island home. Half myth, half ornithological absurdity, it is a tough little survivor that asks nothing of anyone and prefers to be left alone. Not surprisingly, it quickly took over as the nation's mascot of choice, the essence of all that is New Zealand.
As early as 1887, the new Auckland University used the kiwi on its coat of arms, and a rather arthritic looking specimen soon graced the front of the two-shilling New Zealand coin. In 1906 Kiwi Shoe Polish was launched by an Australian in honor of his New Zealander wife, and through the two world wars, when this premium boot polish was in heavy use, its kiwi logo made it into no fewer than 115 countries. Perhaps through this connection, New Zealand soldiers abroad came to regard themselves as "Kiwis," a nickname soon enthusiastically adopted by all New Zealanders.

Eventually, the hunkering bird became a trademark on export products as diverse as spring water, dairy cream and golfing tees. Throughout the country, road signs, street names, billboards, tourist information signs, shop names, municipal garbage bins, even McDonald's hamburger stands, all show the familiar bird. Newspaper headlines routinely refer to "Kiwis do this...," "Kiwis win that..."--an unmistakable form of identity.
Even so, the real bird remains mysterious. Personal encounters in the wild are still the rare province of bushmen, foresters and back-country rangers. The rest of New Zealanders flock instead to a number of kiwi nocturnal houses, ingenious indoor displays that reverse the natural daylight cycle so that cap- tive kiwis are induced to become active during daytime hours. For thousands of people peering daily through one-way glass into artificial twilight to the sound of recorded kiwi calls, this will be their only chance to watch the behavior of their quasi-national bird.
There has never been a more important time for such popular interest because the kiwi's haunting call is fast disappearing. As early as the 1840s, a naturalist of the day noted the birds were declining due to predation by cats and dogs. For a while kiwi "fur" was even sought in large amounts to be used for fashionable muffs and garment trimmings in Europe. Rising concern, coupled with a budding popular love, prompted the government to afford the kiwi com- plete legal protection in 1896.
One hundred years later, the kiwi, secretive as ever, has been slow at giving out details of either its life cycle or its plight. Lulled by its official protection and New Zealand's impressive record at setting aside large tracts of virgin forest as national parks and reserves, many assumed the kiwi would be safe forever. Only a few keen observers began noticing over the past few decades that many areas of seemingly unspoiled forest were no longer ringing with kiwi calls.

To find out what was happening, researchers from the New Zealand Wildlife Ser- vice (later to become the Department of Conservation, or DoC) began spending many months each year in the rugged mountains and rain-drenched forests, painstakingly gathering data on things like territory size and habitat requirements, feeding and breeding biology, and conservation threats. Piece by piece, they assembled a new picture of the kiwi, with some startling new twists.

Kiwis may survive 30 to 40 years, but ferrets,introduced by people from failed fur farms, as well as weasels and other alien predators, have up--set the natural scheme. Although adult kiwis are feisty enough to hold most of these animals at bay, the kiwi's Achilles' heal is its totally unorthodox breeding system. Because the incubating father leaves the nest unattended to feed, predators often cash in on his absence. And because baby kiwis become independent when only one-eigth of their parents' size, they make easy targets for the alien predators.
The rogue's gallery of kiwi killers includes the Australian brush-tailed pos- sum. A marsupial long thought to be exclusively vegetarian, it was introduced to New Zealand last century as a furbearer. Now scientists have learned that it has a predilection for kiwi eggs.

The stoat, a kind of weasel, may be the most severe threat of all. For the last year, John McLennan of Landcare Research, a government research institute, has been following 13 young chicks. From the day they left their nests, he tracked them via tiny radio transmitters strapped to their legs. McLennan and his colleagues tagged six of the chicks on a large forested peninsula where the biologists also eliminated as many wild stoats as they could. The other seven chicks lived in an area where no stoat-control work was done. By the end of the first year, five of the six chicks where stoats had been controlled had survived, but not one of the other seven had lived.

To save the species, the Department of Conservation, with support from the non-government Royal Forest and Bird Society and strong sponsorship from the Bank of New Zealand, five years ago launched an ambitious Kiwi Recovery Program. Under the leadership of kiwi research veteran Hugh Robertson, its initial task was to assess numbers, individual status and the main causes of threat. A glum picture quickly emerged: Kiwi populations, which once may have been as high as 12 million, are currently down to fewer than 80,000, and drop- ping fast.
But at least the tables are beginning to turn. The key, says John McLennan, is to establish safe population reservoirs--pockets free of predators such as stoats--for each genetically distinct type of kiwi. As 82-year-old Arthur Cowan, farmer and New Zealand conservationist of great note, put it, "Now we know what to do, all we need is to do it."
As the facts about the kiwi's plight have become known, more people than ever are getting involved to help. One rural development project prevents tenants from owning dogs or otherwise engaging in activities detrimental to the resi- dent kiwis, for instance. Rural people whose livelihoods intertwine with kiwis are also stepping forward. "Every day, foresters are coming to us to find out how to protect the kiwis within their tree plantations," says DoC's Robertson. "Pig hunters are promising not to allow their dogs to run wild, and farmers are helping locate remnant kiwi populations."

Meanwhile, captive programs, like one at the small town of Otorohanga, con- tinue to educate the public about the kiwi's needs. Injured birds brought to these facilities are nursed back to health and paired up with off-exhibit residents to breed.

For me last year, the Otorohanga center offered an unhoped-for opportunity to observe kiwis up close. Sitting quietly in an outdoor pen at dusk, I waited for the resident pair to emerge from a daytime slumber. The first reaction of the birds was to check me out. After carefully sniffing my feet, tripod and other gear, they went about their business. For hours, they snuffled in the dampest patches under trees and thickets, constantly probing the earth. Often they buried a beak right down to the hilt. Then up came a rapid succession of worms, beetles and other invertebrates--a menu that in the wild also might have been accompanied by land snails, fresh-water crayfish and fruits and ber- ries.

Because the captive pens are nowhere near as large as wild territories, these kiwis also receive a supplemental formula made of fine ox heart strips (resem- bling earthworms), cooked oats, raisins, tofu and various chopped vegetables. By hiding a small amount of this food under leaf litter, I was able to confirm the mind-boggling accuracy of the kiwi sense of smell. The birds located my hidden morsels as quickly and unerringly as trained bloodhounds.

Here at Kiwi Town, as Otorohanga is now often called, I met a fresh baby kiwi, Number 78 in the births ledger, as curator Eric Fox gently lifted it out of the incubator for its first view of the world. It was "all wired and streetwise," as Hugh Robertson had described baby kiwis to me only a few weeks earlier--so spirited that I was instantly encouraged that its species will stay with us for a long time. As I approached for a photo, Number 78 faced me squarely. Although it was barely able to stand, it hissed and growled--not a bad sign for an un-bird in trouble.

COPYRIGHT 1997 National Wildlife Federation
COPYRIGHT 2004 Gale Group

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