Kea

The Kea is the world's only true alpine parrot, a big olive-green bird that makes its living among the peaks, glaciers, and beech forests of New Zealand's South Island. Perched on a rock it can look almost drab, but the moment it opens its wings it flashes brilliant orange-red underwing patches, one of the most dramatic reveals in the parrot world. Add a long, wickedly hooked bill and a swaggering, curious walk, and the Kea is unmistakable.

What really sets the Kea apart is its mind. In problem-solving experiments Keas rank among the most intelligent of all birds, solving puzzles, using tools, and cooperating in ways usually associated with crows and great apes. In the wild that intelligence shows up as relentless, playful investigation of anything new: backpacks, windshield wipers, ski-lift padding, tents, and hiking boots have all been dismantled by curious Keas. That mischief made them famous with tourists but also brought them into conflict with farmers, and for roughly a century a government bounty was paid on Kea beaks, killing tens of thousands of birds. Fully protected since 1986, the species is now listed as Endangered by the IUCN, threatened by introduced predators and lead poisoning, and the remaining wild population is thought to number only a few thousand birds.

Look for a large, robust parrot, roughly the bulk of a big crow, with olive-green body plumage in which each feather is edged in black, giving a neatly scalloped look. The long, narrow, strongly hooked grey-brown upper bill is distinctive even at a distance, noticeably longer and more slender than the bill of its forest cousin the Kaka. In flight the wings flash vivid orange-red underneath, and the rump shows a dull reddish wash. Young birds have yellow around the eye, cere, and bill base that fades with age. Behavior is a field mark in itself: no other bird in New Zealand's high country walks up to people, tilts its head, and starts testing your gear with its beak. Males and females share this plumage, but males run larger and carry a noticeably longer, more strongly curved bill, while juveniles show bright yellow skin around the eye and at the base of the bill that fades to grey over their first few years.

The Kea is named for its signature call: a loud, drawn-out, wailing keee-aaa that rings across mountain valleys, often given in flight. It has a wild, slightly mournful quality, and once heard echoing off a cirque wall at dusk it is not easily forgotten. Both the common name and the Maori name are direct imitations of this cry.

Beyond the classic scream, Keas have a rich vocabulary of trills, chuckles, whistles, and mewing notes used in close social contact. Most remarkable is their warbling play call: researchers have found that broadcasting a recording of it can put nearby Keas into a playful mood, prompting them to start tumbling and tussling, roughly the parrot equivalent of contagious laughter. Around huts and car parks, listen for quiet muttering and squeaky notes as birds work over an interesting object.

The Kea is endemic to New Zealand and confined to the South Island, where it lives along and around the Southern Alps and other mountain ranges from roughly the Kahurangi and Nelson Lakes region in the north down through Arthur's Pass, the West Coast, Aoraki/Mount Cook, and Fiordland in the south. Its total range covers a large area of rugged country, but the birds are thinly spread across it.

Habitat runs from southern beech (Nothofagus) forest on steep valley sides, up through subalpine scrub and tussock grassland, to bare rock, scree, and snowfields above the treeline, terrain no other parrot on Earth occupies. Keas are resident year-round but range widely with the seasons, moving between altitudes as food comes and goes, and individual birds can travel many kilometers in a day. They are famously drawn to human activity, so ski fields, alpine car parks, road passes, and backcountry huts are reliable places to encounter them, especially in winter when natural food is scarce. If you want to see one in the wild, Arthur's Pass National Park, the Homer Tunnel area on the Milford Sound road, and South Island ski fields in the colder months are among the most dependable spots, and birds are often most active early and late in the day. Never feed them, and keep food and gear secured, because food-conditioned Keas are far more likely to be harmed by cars and by conflict with people.

Keas are true omnivores and opportunists, a necessity in mountains where food is patchy and seasons are harsh. The bulk of the diet is plant material: leaves, buds, shoots, roots, berries, seeds, and nectar from dozens of alpine and forest species. The long hooked bill doubles as a digging tool, and Keas will excavate soil and rotten logs for beetle larvae, grasshoppers, and other invertebrates, including the grubs of large native beetles.

They also readily scavenge carrion such as dead deer, chamois, and sheep, and this taste for animal fat lies behind their most notorious habit: some Keas learned to land on live sheep and tear into the fat over the kidneys, occasionally causing wounds that killed the animal. Real but relatively uncommon, this behavior triggered a bounty that lasted from the 1860s until the early 1970s and cost the lives of an estimated one hundred thousand or more Keas. Around people, Keas boldly raid rubbish bins, picnic tables, and unattended packs, and feeding them junk food is strongly discouraged because it worsens conflict and harms the birds.

Unusually for a parrot, the Kea nests on or under the ground. Pairs choose a cavity among boulders, under tree roots, in a hollow log, or in a natural burrow, usually on a steep forested slope below the treeline, and the same site may be reused for many years. The nest chamber, reached by a tunnel that can be a meter or more long, is lined with sticks, moss, lichens, and wood chips.

The female lays roughly two to four white eggs, typically between the middle of the year and midsummer, and incubates them alone for around three and a half to four weeks while the male brings her food. Chicks develop slowly, staying in the nest for about three months, exceptionally long for a parrot, and that long stint in a ground burrow makes eggs, chicks, and brooding females terribly vulnerable to introduced stoats, possums, and rats. Predation at the nest is considered one of the main drivers of Kea decline, and monitored nests in areas without predator control often fail at high rates. Pairs generally attempt one brood per year, and young birds may not breed until they are several years old.

• Kaka: A closely related forest parrot of New Zealand, browner with crimson underwing and belly, a shorter bill, and lowland to montane forest habitat rather than the open alpine tops
• Kakapo: New Zealand's flightless, nocturnal parrot, moss-green and far bulkier, sharing the country but living on the ground in forest rather than the mountains