Last year, Allan Mueller thinks he saw the elusive ivory-billed woodpecker. The wildlife biologist wants to make sure of it this winter.

Mueller plans to head back into the swamps of eastern Arkansas with a scaled-back search team consisting of 26 volunteers and three expert field biologists.

Searchers will begin their work in the Big Woods on Saturday. The campaign will run through the bird's nesting season in March and April when the ivory-bill is most active, Mueller said.

he huge bird was believed to be extinct until a sighting four years ago stirred national experts and federal funding to launch a full-blown campaign to verify the bird's existence and study its habitat.

For want of a clean photograph or audio recordings of the bird's distinctive sounds, searchers have been unable to convince fellow scientists that the bird has survived years of land development and loss of habitat.

Over the last four years, The Nature Conservancy in Arkansas, where Mueller is avian conservation manager, along with the Cornell Lab of Ornithology, the Arkansas Game and Fish Commission and the Arkansas Audubon Society have collaborated to study the ivory-bill in Arkansas and enlist other groups to scout potential habitats in other Southern states.

Besides Arkansas, researchers say the bird has been seen and heard in the swamps of northwestern Florida. A Cornell team will soon begin looking in Florida and travel to Arkansas and elsewhere in the Southeast in hopes of spotting the bird.

Mueller reminds fishermen, hunters and the general public that they can help, too, by calling his office if they have a sighting. An anonymous donor has pledged a $50,000 reward to anyone who leads the team to a live ivory-bill, he said.

The Big Woods swallow up the Cache River National Wildlife Refuge, where kayaker Gene Sparling says he spotted the bird Feb. 11, 2004, and Cornell University experts made subsequent sightings. Since then, searches have been made in about 83,000 of the 550,000-acre woods.

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