NATIONAL BRIEFING / ALASKA

Alaska’s Rat Island is finally rat-free, 229 years after a Japanese shipwreck spilled rampaging rodents onto the remote Aleutian island, virtually destroying the bird population.

After dropping poison from helicopters for a week and a half last autumn, there are no signs of rat life, and some birds have returned, the U.S. Fish and Wildlife Service reports.

Rats have ruled the island since 1780, when they jumped off a sinking Japanese ship and terrorized all but the largest birds on the island. The incident introduced the nonnative Norway rat -- also known as the brown rat -- to Alaska.

The $2.5-million Rat Island eradication project, a joint effort of the federal government, the Nature Conservancy and Island Conservation, is one of the world’s most ambitious attempts to remove destructive alien species from an island.