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The Return of "the Wanderer"
by Matt Olear

“Capable of flying at tremendous speeds and executing astonishingly agile maneuvers, the peregrine falcon is a true ruler of the air, fully worthy of its fame as a raptor of unequaled predatory abilities.”
— Noel and Helen Snyder,
Raptors: North American Birds of Prey

The piercing cries drifted up the valley, penetrating the dense fog as we headed down the side of the mountain ridge. Winding our way furtively through rain-soaked trees, we paused to watch and listen. Perched on the lip of a cliff ahead of us were two wooden boxes, shrouded in the morning mist. Contained in one of those boxes were the reasons for our excursion into the mountains overlooking Harpers Ferry, West Virginia, that mid-June morning. Three female peregrine falcons (Falco peregrinus) were about to be granted their freedom.

Three male peregrines had been released ten days earlier, and the cries of the females at our approach had them buzzing excitedly about the hazy treetops. Trying to keep an eye on the birds’ silhouettes, I peered over the cliff but was unable to see the Potomac River meandering far below. Although the weather and foggy conditions delayed the females’ release several days, it was decided that they would be fitted with the solar-powered satellite transmitters that scientists hoped would track their wanderings for the first years of their new lives. One by one, the falcons were carried from the box to a level area on the ridge, each a raucous bundle of feathers and talons. Throaty, high-pitched screams bespoke of the falcons’ indignation and ruffled pride. Up close, their most striking feature was the large, dark eyes shining out from their chocolate brown heads and boring into me. After being hooded to keep them calm, a transmitter, about two inches in length and weighing about an ounce, was strapped to each falcon’s back with waterproof neoprene and polyester straps. They are designed to stay on for life, but will probably be taken off once the birds select breeding territories.

This release is part of a project that began in 1996 when Shawn Padgett, a research associate for the College of William & Mary’s Center for Conservation Biology (CCB), discovered that many falcons that hatched in nests on bridges were not fledging successfully. It turns out that falcons in these nests often drown while learning to fly. Bridge nests, located directly over water, offer young falcons few places on which to perch during their critical first flights. Padgett estimates that in Virginia at least 80 percent of peregrines born on bridges die as a result of drowning.

In addressing the issue, Padgett devised a plan to take a selection of falcons hatched in bridge nests and release them in areas of the Appalachian Mountains where the species originally nested. Not only would this solve the problem of high mortality in these nests and give the young birds a better chance to survive, but it would also allow the CCB to resurrect its falcon reintroduction program, which had ended prematurely in 1993 as a result of lagging funds. Moreover, the CCB could now use a wild peregrine population for reintroduction rather than captive-bred falcons, significantly reducing the cost of the project. Padgett first consulted with Mitchell Byrd, Director Emeritus of the CCB, and then took his idea to the Virginia Department of Game and Inland Fisheries. Despite initial skepticism regarding the exceedingly high mortality rate of the bridge-born birds, the program was approved. The first release occurred in 2000, when eight falcons were reintroduced in Virginia’s Shenandoah National Park.

In 2001, the CCB tracked 11 falcons from Harpers Ferry National Historical Park and Shenandoah National Park, as well as six hatched on specially constructed towers along Virginia’s coast. A glitch in the transmitters’ programming caused them to shut off in November, but by that time the falcons had begun to move south. True to their name, which comes from the Latin word peregrinus, meaning “pilgrim” or “wanderer,” some of the released birds had already traveled great distances, with one from the coast tracked to the Caribbean islands and one from Harpers Ferry last seen near Miami, Florida. Only one bird from this group is still being tracked, and she currently resides near a power plant just east of Baltimore City.

This year, there have been 12 falcons reintroduced in the mountains and a total of 18 are being tracked: nine hatched on coastal towers, five from Shenandoah, three from Harpers Ferry, and the one still being tracked from last year’s effort. As in previous years, those released in the mountains are offspring of pairs nesting on bridges and coastal towers in Maryland and Virginia. So far, 12 of the 18 have been lost, of which four have been recovered. One had a broken wing and will be re-released in Shenandoah after rehabilitation. Padgett believes the others, which include two of the three falcons tracked from Harpers Ferry, are dead. This is a slightly higher mortality rate than for wild first-year raptors that have reached independence.

Those that are still being tracked have dispersed in much the same way as last year’s birds, some having already traveled as far as Long Island, New York; the Ohio–West Virginia border; and the Savannah River, 45 miles northwest of Savannah, Georgia. (The falcon currently residing on Long Island was released in Shenandoah and had originally traveled from Pennsylvania to Vermont, a trip of more than 330 miles, in just two days.) Scientists hope that once these birds reach sexual maturity at two to three years of age they will return to their release areas to nest.

Despite the reduced cost of using wild falcons, the project is far from cheap. The primary expense of the current initiative is the satellite transmitters, which cost about $2,500 per bird per year. That adds up to about $45,000 this year alone, not including the cost of feeding the falcons their diet of farm-raised quail. The project is being funded by a variety of agencies and organizations, including the two national parks, the Virginia Department of Game and Inland Fisheries, the Dominion power company, the U.S. Fish & Wildlife Service, and NASA. As fascinating as it is, this project is only the latest chapter in an epic tale of conservation and wildlife management—a decades-long struggle to save the American peregrine falcon from extinction.

The Peregrine
The Potomac River cuts a swath through the Appalachian Mountains, forming the border between Maryland and its neighboring states to the south and west on its way toward the Chesapeake Bay. Where Maryland, Virginia, and West Virginia meet, it encounters the Shenandoah River, creating a scenic vista that Thomas Jefferson declared was “worth a voyage across the Atlantic.” There, the Potomac has carved a series of sheer granite cliffs wooded with chestnut oak, maple, and pine. Rising 900 feet above the river’s eastern bank is Maryland Heights, a towering wall of rock and woodland overlooking the town of Harpers Ferry. The first written record of peregrine falcons breeding in Maryland was on Maryland Heights in 1883. At that time, the Potomac was dotted with peregrine falcon nests or “eyries,” as were other eastern North American rivers like the Connecticut, Hudson, and Susquehanna. In 1952, it was the last known nesting site in Maryland, as peregrines quietly vanished from the state and eventually the entire eastern United States. Fifty years later, I stood on the cliffs of Maryland Heights and observed one step in the effort to return the peregrine to its original breeding range.

The peregrine falcon can be found breeding on every continent except Antarctica. It is a bird of wide-open spaces, nesting predominantly on cliffs overlooking rivers and lakes, on coastal palisades, and in mountains. It builds no nest, but lays its eggs in a shallow depression or “scrape” on a rock ledge. The peregrine is a medium-sized raptor measuring 15 to 21 inches in length with a wingspan of 40 to 45 inches, and weighing anywhere from about one to two and a half pounds. The peregrine’s most distinctive feature is the dark plumage that covers its head and extends down through its eyes to its throat, giving the falcon a hooded appearance. As with most raptors, the male peregrine is smaller than the female, in this case by about one-third.

The peregrine has been called “the world’s most perfect flying machine,” and like other falcons, it is built for speed and maneuverability. A perfectly designed aerial predator, the peregrine is streamlined and aerodynamic, with long, pointed wings and a short, tapered tail. The peregrine preys on an extraordinarily wide range of birds, from small passerines to waterfowl and game birds, such as ducks, pheasants, and even geese. As a result of its fondness for waterfowl, the peregrine was once known in America as the duck hawk. A peregrine captures birds in flight using a wide variety of techniques. The most famous of this repertoire is the stoop.

At heights ranging from several hundred feet to well over a thousand, the peregrine surveys airspace below with vision eight times more acute than that of humans. When suitable quarry passes underneath, the falcon tucks its wings close to its body and plummets headlong toward its prey at speeds exceeding 200 miles per hour. The momentum of the stoop adds force to the falcon’s strike, allowing it to capture prey much larger than itself. If the quarry is not killed outright, the peregrine will sever the spinal cord at the base of its victim’s skull using a notch or “tooth” on its upper mandible, a feature common to all true falcons.

Duck Hawks of the Appalachians
Currently, there are 19 recognized subspecies or races of peregrine falcons in the world, varying mostly in size and coloration. North America boasts three subspecies: the American peregrine (Falco peregrinus anatum), which once bred throughout the continental United States and into Alaska, Canada, and Mexico; the tundra or Arctic peregrine (F. p. tundrius) of Alaska, northern Canada, and Greenland; and the Peale’s peregrine (F. p. pealei), inhabiting the northwestern Pacific coast and the Aleutian and Queen Charlotte islands.

The anatum subspecies of the peregrine once nested in mountain valleys and gorges and on cliffs overlooking inland rivers and lakes in North America. Separated geographically by a lack of suitable nesting habitat in the flat grasslands of the Midwest, the eastern and western populations of anatum differed somewhat morphologically, with eastern falcons being significantly larger than those in the west. The eastern falcons of the Appalachians constituted a distinct subpopulation or “ecotype” of the American peregrine as a result of evolution in relative genetic isolation.

The Appalachian peregrines were adapted to life in the northern-boreal and temperate-forest habitat of eastern North America. They were large, dark falcons—nearly completely black on the head and a buff, rufous color underneath, with spotting on the breast and heavy barring below. These falcons were relatively nonmigratory, remaining on their breeding grounds year-round or migrating short distances to the Atlantic coast. Some even took up winter residence in cities like New York and Philadelphia, taking advantage of the feral pigeon (Columba livia) population. With a longer mean wing length than the western anatum and larger feet typical of forest-dwelling peregrines, the Appalachian falcons were some of the largest peregrines on record. As a result of captive breeding and reintroduction, the peregrines that now reside in the East are a genetic mix of falcons from the Canadian and Arctic tundra, western North America, the Pacific Northwest, Spain and the Mediterranean, South America, and Scotland.

Population Crash
The Appalachian mountain chain was once a stronghold for the peregrine in North America. In 1942, University of Wisconsin biology professor Joseph Hickey inventoried 275 nesting sites of the peregrine east of the Rocky Mountains known to egg collectors, falconers, and ornithologists. He estimated there were as many as 350 pairs of peregrines in the Appalachians from Maine to Georgia and Alabama, a figure some biologists now deem conservative.

In the years following World War II, however, local ornithologists and peregrine enthusiasts documented reproductive failure in many historic peregrine eyries in the East. Eyries monitored in Massachusetts, Pennsylvania, and along the Hudson River in New York began to experience difficulty not just in successfully fledging young, but in simply hatching eggs. Then in 1962, more than 20 years after his initial survey, Hickey heard a rumor circulating at the 23rd International Ornithological Congress at Cornell University that not a single peregrine had fledged that year in the northeastern United States. In 1963, after reading a paper by renowned British ornithologist Derek Ratcliffe documenting similar nesting failure in Great Britain, Hickey conducted a review of the same nesting locations he inventoried in the early 1940s. More than 140 eyries were surveyed; none were occupied and not a single adult peregrine could be found. The Appalachian peregrine of the eastern United States had been extirpated. In the West, 80 to 90 percent of peregrine pairs had vanished, and similar declines, though not as dramatic, had occurred in the United Kingdom and across Europe.

In his 1963 article, Ratcliffe hypothesized that the falcons’ disappearance was due to the widespread agricultural use of organochlorine pesticides that began after the war. Further research conducted by Ratcliffe and scientists at the Patuxent Wildlife Research Center in Laurel, Maryland, proved that theory to be correct. The pesticide DDT, and its byproduct DDE, was found to be the main culprit. Stored in fatty tissue, DDT worked its way up the food chain from insects to small birds to falcons and other raptors, becoming more concentrated at each level. In peregrines, DDE caused reproductive failure by mimicking natural hormones and inhibiting the female’s ability to produce the excess calcium needed to form eggs. The resulting thin-shelled eggs broke under the weight of the incubating falcon. Such a precipitous decline in a relatively short period of time did not bode well for the peregrine or its future recovery.

Saving the Peregrine
In 1970, the American and Arctic subspecies of the peregrine falcon were listed as endangered under the Endangered Species Conservation Act. Also in that year, scientists at the Laboratory of Ornithology at Cornell University in Ithaca, New York, established a program to restore the country’s peregrine population by breeding falcons in captivity and releasing them into the wild. The program, headed by Cornell ornithologist and falconer Tom Cade, would eventually become known as The Peregrine Fund. Few people thought the project would be a success, as up until that point no one had been able to consistently breed raptors in captivity. In addition, the reintroduction program was controversial because it used peregrines from different geographic locations, as the anatum subpopulation indigenous to the East had been eradicated. It was decided, however, that by using peregrines from a variety of subspecies sharing similar characteristics with the original Appalachian falcons, nature would select the individuals best suited to the eastern environment.

Despite the challenges, The Peregrine Fund’s breeding program was a success, producing its first 20 young falcons in 1973. The following year, the first attempt to reintroduce captive-bred peregrines to the wild took place on the New Paltz campus of the State University of New York—within sight of the Shawangunk ridge of the Catskill Mountains, the location of several historic peregrine eyries. By 1975, The Peregrine Fund was able to breed falcons on a consistent basis, and a reintroduction effort began in earnest. The Peregrine Fund and the U.S. Fish & Wildlife Service, in cooperation with many state and local agencies in the East, created The Eastern Peregrine Recovery Plan. Originally, 11 regions were designated for peregrine releases, but they were eventually condensed into five: Mid-Atlantic Coast, Northern New York and New England, Southern Appalachians, Great Lakes, and Southern New England and Central Appalachians.

Initial releases occurred at or near historic eyries in the mountains and on cliffs along lowland rivers. It was quickly discovered, though, that at many lower elevation sites the young falcons, lacking the protection of adult birds, were vulnerable to predators, particularly the great horned owl (Bubo virginianus). To counter this, The Peregrine Fund limited cliff reintroductions to higher elevations in the Northeast and began concentrating releases from specially constructed towers on the salt marshes of the Atlantic coast and in urban areas, where great horned owls are less of a threat. Scientists found that not only was the rate of return higher at these sites, but that the falcons’ hunting skills developed more quickly as a result of an abundance of prey.

Although this technique was controversial because falcons had not traditionally nested along the Atlantic coast, it proved to be very successful. The Mid-Atlantic region was the first to meet the recovery quota of 20 to 25 pairs, and the first breeding of the peregrine in the East after DDT occurred at a coastal tower in New Jersey in 1980. That same year, the first active eyrie in the eastern mountains was discovered in Maine, and in 1981 peregrines returned to breed at an historic cliff eyrie at Franconia Notch in New Hampshire. All told, more than 6,000 captive-bred peregrines were released in 34 states between 1974 and 1997—the result of collaborative efforts between federal, state, and local agencies; non-profit organizations; and private citizens. It is easily the most extensive and successful recovery effort ever undertaken on behalf of a single species. Finally, in August of 1999, the American peregrine falcon was officially removed from the Endangered Species List. Currently, there are about 2,500 pairs of peregrines throughout the United States and Alaska, with about 300 east of the Mississippi River, most of which nest on coastal towers or in urban areas on bridges and skyscrapers.

Restoring Falcons to the Appalachians
When scientists began concentrating peregrine releases in urban areas and along the Atlantic coast, it was hoped that falcons released at these sites, or their progeny, would eventually take up residence at historic cliff eyries. To date, a crossover to the Appalachian cliffs has not occurred. Some speculate this is due to the presence of great horned owls or a changing eastern landscape in which many of the falcon’s traditional nesting cliffs have become overgrown with trees. Other scientists believe that it is a result of reintroduced falcons imprinting on their release sites.

Peregrines and other raptors imprint on their natal areas and tend to seek out similar places to breed when they are adults. And, in fact, current cliff eyries occur almost exclusively in areas where mountain releases took place, such as the Adirondacks in New York, Acadia National Park in Maine, the White Mountains of New Hampshire, and the Green Mountains of Vermont. But with the exception of about a dozen eyries in the Great Smoky and Blue Ridge Mountains of Tennessee and North Carolina, the falcon’s old haunts in the central and southern Appalachians remain vacant. Despite federal de-listing in 1999, the peregrine is included on the state endangered or threatened lists in these regions.

As part of the original recovery effort, the CCB, the North Carolina Wildlife Resources Commission, and the Tennessee Wildlife Resources Agency released peregrines in the southern Appalachians under the supervision of The Peregrine Fund. Since many potential release sites were unsuitable due to great horned owl presence or human disturbance, they released falcons from towers placed in high elevations in the vicinity of available nest sites rather than directly on cliffs.

The Peregrine Fund discontinued its involvement in the eastern recovery effort in 1992, and the reintroduction program in the southern Appalachians ended one year later when funds ran out. Despite its premature end, the project was not without success. In the mid-1990s, falcons returned to breed in Shenandoah National Park following an absence of more than 30 years. Several pairs were also established in the mountains of West Virginia. However, these peregrines eventually disappeared, and the central and southern Appalachians remain well below the initial goal of 20 to 25 pairs for each of the five recovery regions.

It was then in 1996 that Padgett conceived the idea for the project that led me to be standing on the cliffs of Maryland Heights on that unseasonably cold and wet June morning. Thanks to banding and satellite-tracking efforts, scientists are beginning to learn about the habits and ecology of this growing eastern falcon population. By using satellite telemetry to track the falcons’ movements, Padgett and the CCB hope to learn how many of their birds survive to adulthood, if and where they migrate, and what breeding locations they select. In addition, questions remain as to whether or not falcons will eventually return to vacant cliffs on their own and if great horned owls will be a deterrent. “I think over time we’ll see that falcons bred in the coastal plain may start to venture toward historical mountain ranges on their own,” says Craig Koppie, an endangered species biologist with the U.S. Fish & Wildlife Service. Although Cade is less convinced of this, he believes that the current cliff-nesting population will eventually expand into some of these areas. Cade also acknowledges that peregrines have returned to nest successfully on cliffs where owls had once ravaged reintroduced falcons. Two pairs of peregrines now nest on the Shawangunk ridge of the Catskill Mountains in New York, where owls had thwarted releases in the 1970s. And this spring, for the first time in more than 50 years, peregrines returned to nest on a cliff in Massachusetts, without human intervention.

These questions, however, can only be answered over time, and the ultimate goal of this project is to see what Cade and his colleagues had hoped for in the beginning: the peregrine once again occupying its rightful place in the rugged mountains and towering cliffs of the Appalachians. Padgett thinks Harpers Ferry is a good start. “My hunch,” he says, “is that if we continue to hack [release falcons] in Harpers Ferry we will have falcons there in a couple of years. It is prime falcon habitat with the cliffs and the river. It’s a beautiful area.” His hunch is bolstered by the fact that others have had success with similar projects. A reintroduction program conducted recently along the upper Mississippi River succeeded in bringing peregrines back to cliffs in Minnesota, Wisconsin, and Iowa.

Initially begun as a two-year project, Padgett and Koppie say that they will continue to release falcons until peregrines return to Harpers Ferry and Shenandoah. The two parks are more than willing to do what it takes to see the falcons come back. According to Bill Hebb, Harpers Ferry Natural Resources Manager, the park is thrilled at the prospect of having falcons return to nest and will close a popular scenic-overlook trail during the breeding season if peregrines take up residence on the cliffs. Currently, Maryland has 12 to 14 pairs of peregrines and Virginia has 17, all of which nest on buildings, bridges, or coastal towers. Scientists believe it is likely that there are a few active eyries in remote areas of the mountains that have not yet been found, but there have been no reports of peregrines on cliffs in these states, or in Pennsylvania and West Virginia. This project hopes to change that.

When you ask someone involved in the efforts to restore the falcon why the peregrine has inspired so many people to come to its aid, not only in modern times but also throughout its long association with man as a favored bird in falconry, the common answer addresses the obvious aesthetics: the peregrine’s beauty, its speed and grace, its prowess as a hunter, its mastery of its element. But the one answer that stands out is the bird’s mystique—the idea that it is a unique and extraordinary bird. It is because of this quality that the epic story of the peregrine is not over. As long as it continues to inspire, there will be people who see to it that the birds endure.

—Matt Olear, an avid follower of peregrine falcon progress, is a media specialist and writer for FONZ.

Raptor Conservation at the Zoo

ZooGoer 31(6) 2002. Copyright 2002 Friends of the National Zoo. All rights reserved.

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