Perigrin falcons are equipped with full-color vision, with eyes specially adapted to permit quick focus adjustments while moving at high speeds. MIKE COHEA - Ravalli Republic

Peregrines are crow-sized raptors that prey primarily on other birds, such as swallows and small waterfowl like teal. A peregrine will hunt from the wing, diving at speeds up to 200 mph towards its chosen prey, hitting it with its feet, then turning to catch it in mid-air. These skills make peregrines popular falconry birds, successfully used for hunting. Kate Davis, executive director of Raptors of the Rockies, says her favorite hunting companion is Sibley, her peregrine falcon.

Sibley has been known to “stoop,” or dive, at birds as big as wild turkeys, and once plucked a mallard she had hit from the mouth of Davis' English setter, who had retrieved the duck from the water.

Davis doesn't hunt Sibley when eagles are around, however. Great horned owls and eagles will attack peregrines, and golden eagles' nesting sites have kept peregrines out of certain canyons this year.

They have, however, made homes in 11 other local canyons this summer.

Peregrines had disappeared from the Bitterroots when biologist, John Ormiston, first learned about efforts to reintroduce the birds in the state. In the early 1980s peregrines were successfully reintroduced in the Centennial Valley in southwest Montana. Hopeful the reintroduction could be imitated here, officials from the Bitterroot, Beaverhead, Lolo and Kootenai Forests brought people involved with peregrine reintroduction to western Montana to check out what Ormiston calls the “really good looking” peregrine habitat in the Bitterroot canyons.

The habitat consists of vertical cliffs with south-facing walls and ledges with sheltering overhangs that provide ideal space for peregrine nests, called aeries, Ormiston said.

The birds typically nest on the top third of tall cliffs; but unlike the nest of many other birds, a peregrine aerie is simply a cleared area on a ledge, sometimes surrounded by a few pebbles to keep the eggs from rolling around, according Ormiston. The Bitterroot canyons' cliffs are within easy flying distance of the Valley, providing ideal falcon hunting habitat.

Just over 15 years ago, there were no peregrines in the Bitterroots. Their recovery has been strong thanks to the natural magnificence of the Bitterroot Mountains - and a little help from a concerned wildlife biologists.

The very first reintroduction effort in the Bitterroots was successful. In June 1989, Ormiston and a team of Forest Service biologists brought five peregrine chicks to the Painted Rocks Reservoir in a four-by-six foot box. Known as a “hack box,” it had a screened front and a hole for feeding at the top.

The 35-day-old birds' visible imprinted environment was the perfect peregrine habitat, and the biologists were careful to be as invisible as possible to the chicks. They fed them quail everyday for two weeks, then, in mid-July, they removed the screen so the fledgling chicks, just 49 days old, were free to fly.

Almost all of the birds flew the first day, said Ormiston. Although their flight skills are limited as fledglings, their instincts tell them how to fly. The chicks have to learn how to land, however, and how to hunt. The biologists fed the birds less and less frequently as the peregrines learned to identify the passing swallows and swifts as food and began practicing the hunt. By mid-August, the fledglings were no longer returning to the hack box for meals, and the biologists lost track of the newly wild birds.

At the end of the summer, peregrines typically begin following prey south, some migrating to the southern U.S., others traveling a far as South America, and they return to their fledgling sites to begin mating around mid-March.

Because peregrines do not mate as yearlings, the biologists did not expect to see any falcons returning to the Bitterroots in 1990. They successfully “hacked” another six birds that year.

By 1991, biologists found evidence of a local, natural peregrine aerie. From 1991-1993, biologists' hacking efforts were only about 50 percent successful because returning peregrine adults were interfering with the chicks. As far as the reintroduction effort was concerned, that sort of interference indicated early success, despite the loss of some chicks, because it meant the falcons were re-establishing themselves in the area. Ormiston and his colleagues decided to quit hacking. “Then we switched into recovery mode,” he said.

The first wild pair of peregrines nested near Painted Rocks Reservoir in 1991 and raised two chicks there.

The next confirmed wild aerie was in Blodgett Canyon in 1993, and peregrines were active in the same hole for four or five years there. Since then, they have changed aerie sites in that canyon at least three times, perhaps due to climbing activity in the area.

Peregrines will tolerate activity below them, but are sensitive to disturbance above their aeries, Lockman said. For instance, an aerie site established at Sweeney Creek a few years ago was not re-nested in any subsequent years. Lockman speculated that because the cliff was actually under a switchback road littered with tires and beer cans and popular with recreational shooters, the falcons decided not to attempt to nest there again.

“When climbers get too close,” Lockman added, “obviously, the birds get upset.” Most aerie sites in the canyons don't see much rock climbing, Lockman said, so there hasn't been the conflict between climbers and raptors that has become a problem in other parts of the country.

Blodgett Canyon, probably the most popular climbing site in the Bitterroots, has seen an unusual amount of peregrine nest movement and a higher rate of nest failure, although both Lockman and Ormiston acknowledged that there is no clear connection between climbing activity and falcon nesting in that particular area. In other places around the country, however, such as Rocky Mountain National Park, climbing has been deemed a significant threat to the reproduction of certain raptors and recreational use of some cliffs has been restricted.

So far, the peregrine population in the Bitterroot area has grown to a stable level. Three active nests were spotted in 1996, four in 1998, and seven in 2000. This year, there were 11 identified aeries, down from the peak number, 12, recorded last summer.

Of the 23 Bitterroot canyons, 13 have hosted known peregrine aeries, said Lockman. This year, aeries range as far north as Carlton Creek and as far south as the West Fork Ranger District. The original Painted Rocks site has been home to aeries every year for the last fifteen years, although the specific nest site has moved a few times, said Ormiston.

The Bitterroot recovery effort parallels state-wide reintroduction success, according to Jay Sumner of the Montana Peregrine Institute. The Institute contracts with the state to survey peregrine falcon numbers and keep federal and state agencies posted on population trends. Keeping accurate data, Sumner said, will help prevent serious drop in falcon numbers like that seen in the 1960s, and management decisions can be based on solid population data collected over a long time.

In 1999, the Institute reported only 15 falcon nests across Montana. Although numbers for this year aren't final, Sumner speculated that there will be 68 aeries state-wide, with many successful nests right here in the Bitterroot canyons.

Reporter Brooke Barnett can be reached at 363-3300 or bbarnett@ravallirepublic.com

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