THE tiny back-country plane aims its nose at the steady ''beep, beep, beep'' picked up from a radio-collared wolf hidden somewhere within the deep, snow-covered folds of central Idaho's wilderness.
The beep grows louder, pounding rhythmically into the cockpit as pilots Fred Reed and Sam Bennett bank the plane over the ridge 300 feet below. With one eye on the steep ridges that enclose the narrow canyon, the two pilots peer through the tree tops below.
''There he is!'' one shouts. They have spotted ''Tree,'' a 98-pound black male wolf trotting through the conifers.
''Tree,'' named by Boise High School students, is one of 15 wolves released in January into central Idaho's wilderness by the US Fish and Wildlife Service (FWS) as part of one of the nation's most visible -- and contentious -- animal reintroduction plans.
FWS plans to introduce 30 more wolves into the Rocky Mountain region over the next three years in an effort to restore the endangered predator to its native habitat.
Mr. Reed, the owner of Western Air Research in Driggs, Idaho, is the man hired by the US Fish and Wildlife Service to keep tabs on the wolves. He and his equipment have become the eyes for many who are watching the controversial plan. The view from his cockpit offers a window into the challenges involved -- logistically and politically -- in reintroducing such a predator to the wild.
Environmentalists cheer the wolf reintroduction, saying it will restore a natural balance to the 4 million acre target area not seen since the 1920s, when many ranchers began killing the predators as they attacked cattle and sheep. Most ranchers today revile the plan, fearing increased predation by the animal that is rivaled only by the bear in its place atop the food chain. Others criticize the plan's $15 million price tag.
Tracking is tough work
Dodging arctic squalls, outrunning driving snow storms, and being bounced around by quirky mountain drafts, Reed says keeping up with the itinerant canines is ''one of the most challenging jobs I've ever done.''
Finding the wolves in the nooks and crannies of the 11,000 foot mountains requires a bit of wolf logic combined with a lot of guess work, Reed says.
When released, the wolves did just what biologists expected them to do: they headed north toward their Canadian homeland, where FWS originally snared them.
But then the wolves slowed down and started investigating their new territory. In the two months since their release, the 15 wolves have ranged from southwestern Idaho to western Montana, but none have returned to Canada.
On Jan. 28, Reed spotted a female wolf, tagged B13 by FWS, roaming a few miles from a livestock herd near Salmon, Idaho.
But before Ted Koch, head of Idaho's wolf recovery program could plan a response the next day, she was found shot dead, having dined on a calf she killed. No one knows who shot the coyote-colored wolf.
Under a compromise that has placated few ranchers, FWS has said the wolves could be killed if they were attacking livestock.
No other livestock attacks have been reported, but Reed says that it's hard to tell just where he will find the wolves from week to week. Libre, a female wolf who has zigzagged her way across 350 miles -- farther than any of her counterparts -- was spotted Feb. 27, curled up 100 yards from the top of a chairlift on the Idaho-Montana border. The ski resort wasn't open that day, Reed says.
Another wolf, B14, couldn't be found at all on a Feb. 20 flight. A week later, though, Reed found the 101-pound gray male more than 100 miles from where he had last been located 18 days earlier.
Just a week later, on Mar. 9, Reed found B14 on the Idaho-Montana border. Mr. Koch said the 70 miles traveled by B14 was not unusual even for a naturalized wolf.
Actually sighting a wolf is lucky, Reed says, leaving ''Tree'' behind and going after another. He did not have to wait long. Picking up a distant beep, the computer told him it was ''B2,'' dubbed Chat-Chaaht by students in Lapwai, Idaho. He found the wolf about 100 yards from a herd of elk.
Proponents of the plan say wolves' predation will help cull burgeoning elk herds in the region. Elk, deer, and Bighorn sheep are the wolves' main prey in their new home.
''I think Mr. Wolf is right in this area over here,'' he says, circling over a south-facing bowl dotted with fir trees and bare ground.
Half a dozen circles around the trees could not scare up the gray wolf camouflaged by bare ground and trees and probably basking in the morning sun. Unable to see him, Mr. Bennett took a photo of the location, then moved on.
By 5 p.m., the pilots had located all but four of the wolves. B8 and B6, a male and female that have been traveling together since Feb. 5, were just a few miles miles from their release site at Indian Creek and 37 miles from their location a week earlier. Koch is hopeful that the pair has mated. Breeding typically occurs in January or February. Pups are born in the spring.
Reed says a prolonged spell of bad weather that kept him grounded for 11 days was a turning point in the study. He found that the northbound wolves had generally started heading back to their release site at Indian Creek.
While his job is ''just to collect data,'' Reed says that after months of scanning the rugged mountains of Idaho and Montana and second guessing wolves, he can't help but speculate on their movement and what it might mean.
''After the storm we went back out and started locating critters, and it really blew me away,'' he says.
''All these wolves, hundreds of miles from each other suddenly decided to turn around and head back to the release site,'' he says. ''What is it that triggered them to turn around all at the same time?''
Until the wolves settle down, Reed has plenty of time to wonder about what the wolves are doing and why. He is not alone. Environmentalists, ranchers, and others are all wondering and watching with him.