Rare North Island brown kiwi is hatched at the National Zoo

Their bones are solid, not hollow like those of most birds. Their feathers resemble hair, and their nostrils are located at the tip of their long beaks. Nocturnal, New Zealand kiwis live by smell. At night in the outback, one can hear them sniffing for earthworms.

In February, the National Zoo welcomed this “most unbirdlike of birds,” with the hatching of a rare North Island brown kiwi, Bird Keeper Kathy Brader says. “This hatch bumps the number of kiwis in America up to 17.”

Fewer than 40 of these odd flightless birds exist outside New Zealand. Of those, the majority can’t—or won’t—breed, making each new captive birth something to, well, crow about.

The egg was laid by Nessus, the Zoo’s adult female kiwi, on Dec. 11. After allowing male kiwi, Maori to sit on the egg for 29 days, Brader removed it and began nurturing the egg herself in an electric incubator.

Following New Zealand’s protocol for kiwi eggs, Brader drew pencil lines on the shell, dividing it into quarters along its oblong axis. She rotated the egg a quarter turn four times each day in the incubator. Twice a week, she candled the egg, shining a bright light behind it and illuminating the yolk to document the growth of the air sac—an indicator of fertility and health. Each day, she cooled the egg for one hour, as the protocol recommends. A healthy chick hatched Feb. 13.

“The kiwi’s egg grows to 20 percent of the female’s body weight,” Brader says, giving it one of the largest body-to-egg ratios of any bird. The large egg size allows a kiwi hatchling to grow a large internal yolk sac—64 percent of its birth weight—in essence, a refrigerator of nutritious snacks available 24/7. This gives the baby bird a window of eight to 11 days before it has to eat. Kiwi chicks receive no food or nurturing from their parents.

What Brader likes best about kiwis is their spirit. “They’ve got the most attitude of any bird in the world,” she says. Soon, the baby kiwi will lose its gentle demeanor and turn into a feisty, loud creature.

For all their spiritedness, kiwis cannot stand up to introduced mammal species, such as dogs and rats. In 1987, populations of New Zealand’s North Island brown kiwi, one of five kiwi species, was 68,000. Today, it stands at 24,000.

Brader wants more zoos to breed kiwis and create a self-sustaining population of North Island browns in U.S. zoos. “What better way,” she says, “to ensure that generations of Americans get a peek at this extraordinary creature.”