February 28, 2007—You might call it a cry for help or perhaps a voice from the past. But for scientists who recently recorded the shriek-like call of one of the world's rarest birds, the sound is music to their ears.

The newly captured call belongs to the Sumatran ground cuckoo, a large, colorful bird so scarce that it was thought to be extinct until just ten years ago.

Since the species was rediscovered in 1997 on the Indonesian island of Sumatra, scientists have struggled to learn more about the secretive cuckoo (see Indonesia map).

Researchers got a chance to do just that when a trapper recently turned over an injured cuckoo to biologists with the Wildlife Conservation Society (WCS) in Indonesia.

As the biologists tended to the bird's wounded leg, they also set about studying its habits—including its unusual call.

Described by scientists as a "scream," the guttural caw sounds more like a man mocking a bird than a bird itself (hear the cuckoo's call). But the sound will be an invaluable beacon for biologists trying to track the cuckoos in the wild, and it may help unlock secrets of the elusive birds' behavior.

"We were extremely lucky to have recorded the bird's unique call," said Firdaus Rahman of WCS's Indonesia Program in a statement.

"Our team will use the recording to hopefully locate other Sumatran ground cuckoos and to eventually secure their protection."

—Blake de Pastino

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