Night Belongs to the Kiwi

It may look fuzzy and adorable but this New Zealand bird is one tough customer

"Into my field of view," writes Derek Grzelewski, "runs the oddest-looking creature, a shaggy, pear-shaped fur ball, that sniffs and snorts like an agitated hound." Grzelewski has joined ecologist John McLennan in New Zealand's Kahurangi National Park as he studies the elusive kiwi bird. McLennan has been researching these odd, nocturnal hunters for the past 15 years, devoting countless nights to following them through the bush.

In addition to significant discoveries about kiwi behavior, McLennan has discovered that the kiwis are battling for their existence against a formidable foe — and losing. "We are witnessing not just a decline but a nationwide population collapse," he says. Twelve hundred years ago, biologists estimate, there were 12 million kiwis in New Zealand.

Today, there are fewer than 70,000. The major culprit, McLennan has found, is the stoat, a ferocious, newly introduced mammal that is related to the weasel and preys on kiwi chicks up to 17 weeks of age, contributing to the death of 95 percent of them.

Since 1995, McLennan's goal has been to create a stoat-proof enclave. He has chosen the peninsula of Puketukutuku on New Zealand's North Island. Along the entire coastline and major ridges as well as across the peninsula's narrow neck, he set traps. Then, with the help of a professional hunter, he eradicated most of the stoats inside the enclosure. Although stoats remain a problem, close to 60 percent of kiwi chicks on Puketukutuku have reached adulthood over the past four years.

"There is a good chance," reports Derek Grzelewski, "that the kiwi, that adorable and puckish national icon, may soon become an ambassador of ecological restoration."

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