Onward and Upward in the Search for the Ivory-billed Woodpecker

January 2008


Aerial surveys begin in the White River National Wildlife Refuge. Photo by Matt Conner, © USFWS

The search for the Ivory-billed Woodpecker in Arkansas is headed in a new direction: up. Helicopter surveys of the Big Woods began January 28, led by the U.S. Fish and Wildlife Service. More than 125,000 acres of forest in the White River and Cache River National Wildlife Refuges will be surveyed in about 10 days.

“The aerial search is another sampling tool,” says Matt Conner of the U.S. Fish and Wildlife Service. “It won’t be the conclusive yes or no, the ivory-bill is on the White River or on the Cache River—this is just another scientific method of sampling that may show us if some of the birds are there, but we could still miss them.”

“We want to get up in the air to see if it’s possible to locate an Ivory-billed Woodpecker from a different perspective,” says Ron Rohrbaugh, leader of the Ivory-billed Woodpecker Research Project for the Cornell Lab of Ornithology. “When you’re flying 200 feet above the forest canopy, you can cover a lot of area. After three years we’ve covered about 15 percent of the Big Woods on foot. We can do more than that in a couple of weeks with a helicopter.”



Map by Jim Besley, © USFWS

The helicopter will take off from local airports and helipads, depending on the area being searched that day. In addition to the pilot, rotating crews of three people each will be on board—biologists armed with video and still cameras. The aerial observers will use GPS units to mark possible encounters with an ivory-bill or to pinpoint habitat of interest, such as stands of newly-dead trees preferred by ivory-bills. Ground crews can return to those areas for follow-up searches. The helicopter will land every two hours to drop off videotapes for review and to let the crew warm up. “It’s going to be cold up there in an open-door helicopter!” says Conner.

The National Geographic Society is supplying high-definition video cameras and digital still cameras for the aerial surveys and for the remainder of the Arkansas field season. The aerial crew will use an image-stabilization system to get steady pictures and the still cameras have 135-500 mm lenses. The crew has been trained in how to use them at high altitudes and high speeds. If an ivory-bill is spotted, the white trailing edges of its wings will be the key field mark, easily seen from above.

Ground crew members will be positioned near small lakes or other open areas. Crowfoot Lake photo by Abe Borker.

If the searchers see an ivory-bill, the helicopter will stop flying in that area and a field crew will move in to look for the bird and for evidence of its presence, such as tree cavities or feeding sign. The ground crew of seven will be spread out, strategically positioned at small lakes, river bends, power lines, pipelines, and other areas with an open view, equipped with cameras to catch anything that might take flight at ground level. The Lab’s project biologist, Martin Piorkowski, is part of that group.

“We’re focusing on areas lightly searched in the past and areas that have great habitat potential,” Piorkowski says. “We’re looking at prime habitat—the best of the best of the Big Woods. By that I mean areas with big trees, good old-growth canopy, recently-dead trees, and lots of woodpeckers of all kinds.” It’s been especially difficult to get into the North Unit of the White River National Wildlife Refuge because of fluctuating water levels.

The search areas are all public lands except in one case where the landowner requested a survey. Conner stresses that if the endangered ivory-bill is found on private property, no land will be taken. Rather, the U.S. Fish and Wildlife Service will work with the landowner to protect the bird through a Cooperative Conservation Agreement.

Agencies taking part in the aerial surveys include The Arkansas Game and Fish Commission, The Nature Conservancy, the Cornell Lab of Ornithology, the U.S. Forest Service, and others. Aerial surveys have been used successfully to census waterfowl and to locate Red-cockaded Woodpecker cavities, Conner says. “We’re confident these surveys will help us do a better job searching for the Ivory-billed Woodpecker in Arkansas.”


Read a USFWS overview of the helicopter survey. (PDF)

--Pat Leonard