Return to the Heartland
Absent from the Midwest for most of the past century, the regal trumpeter swan is making an impressive comeback
- Gayle Worland
- Jun 01, 2002
SUMNER MATTESON received some conflicting advice before his first trip into the Alaskan wilderness by bush plane in 1989. He'd been told to have a hearty meal before boarding the aircraft; he'd also been told not to. So Matteson went aloft with an empty stomach and, for the next 13 grueling hours, managed to both (a) help further a wildlife success story and (b) keep from passing out.
Matteson, an avian ecologist who heads Wisconsin's trumpeter swan recovery program, was on a mission to inspect and extract precious 12-ounce eggs from trumpeter swan nests in the Minto Flats area of east-central Alaska, home of the largest remaining pocket of these native birds. On annual trips to the flats during the next nine years, Sumner and his colleagues would gather a total of 385 eggs for transport back to his state. Ninety percent of them would hatch in the care of the Milwaukee County Zoo and would soon be returned to the wild in their former Midwest habitat.
At the turn of the twentieth century, trumpeter swans had vanished from America's heartland. But today, thanks to the dogged persistence of wildlife biologists such as Matteson--and funding from both private foundations and state income-tax checkoff funds--the Midwest is home to an estimated 2,400 wild adult trumpeter swans.
"You have to realize this was all a big experiment," says Joe Johnson, chief wildlife biologist at Michigan State University's Kellogg Bird Sanctuary, the focal point for hatching and rearing trumpeter swans for release in Michigan. Now, he says, "We are on the verge of a major conservation success story."
Photo: © RICHARD P. SMITH
WELCOME HOME: Biologists release captive-reared swans (above) at Seney National Wildlife Refuge in Michigan. Thanks mostly to the efforts of state wildlife officials, hundreds of trumpeters have been moved from Alaska to the species' former habitat in America's heartland. The birds have recolonized seven central states.
With their long necks, 30-pound bodies and wingspans that can reach nearly eight feet, trumpeter swans lumber through the air with a forceful grace. The birds, found only in North America, were once ubiquitous throughout the eastern two-thirds of the United States and much of lower Canada. But their size and relatively slow speed made them easy targets for European settlers and market hunters, who shot the swans for meat and exported their skins and feathers. The European craze for swanskin powder puffs, quill pens and feathers for ladies' hats all but wiped out the species by the late 1800s.
In the late 1920s and 1940s, small pockets of trumpeter swans were found in the greater Yellowstone region and near Grande Prairie, Alberta; that combined group is today known as the Rocky Mountain population. Another cluster of wild swans was discovered in Alaska in the 1950s and labeled the Pacific Coast population.
Trumpeter swans select their mates at age two or three, after a lengthy courtship that involves a ritual of synchronized swimming and blowing in the water. By age three to six, the female (or pen) and male (or cob) build an elaborate nest measuring about 6 feet at the base and rising 1.5 feet. The nest, which may remain the pair's breeding spot for a lifetime, often sits atop a muskrat house or on a broad bed of marsh plants surrounded by plenty of open water--creating a private "island" for the family.
The swans are extremely territorial and most demand isolation during the nesting period. Their range in summer can be as large as 150 acres. In winter, they tend to gather in flocks of as many as 60 swans, though each pair and its young remain a tight family unit.
In early May, the pen usually lays three to nine dull white eggs and incubates them for about five weeks. Once hatched in mid-June, the silver-gray youngsters feast on insects, crustaceans and aquatic beetles until they can adopt the plant-based diet of their elders. By the age of four months, weighing 20 pounds or more, the cygnets try their wings, slapping and scuttling over the water as they attempt their first wobbly liftoffs.
Trumpeter swans closely resemble North America's other native swan, the tundra (formerly whistling) swan. The adults of both species are large and white; both species' heads sometimes take on a rust color from the pond bottom, from which they pull succulent plants by submerging their long necks. The trumpeter's dark eyes blend into the uppermost part of its all-black bill; some, but not all, tundra swans have a small yellow patch on the bill near the eye.
Because they so closely resemble the tundra swan, trumpeters can also become casualties during tundra swan hunts, which are legal in the Dakotas, North Carolina, Virginia and a handful of western states. Tundra swans escaped the nineteenth-century decimation of trumpeters because their nesting range lies much farther north. In October and November, the two swans' ranges overlap when the tundra migrates across the Great Lakes region.
Urban dwellers might be more familiar with the mute swan, a slightly smaller all-white swan with a distinctive orange bill. Imported from Europe, mute swans are capable of devouring much of the food stock in a dwindling number of American wetlands, and are considered a pest by some. However, others believe it to be no match for the stronger and more determined trumpeter swan, which will drive away the mute swan if it tries to invade its territory.
As for the look-alike tundra and trumpeter swans, the best--and sometimes only--way to tell the birds apart is to remember what gave the trumpeter its name. One of the most distinctive soloists in nature's wetland orchestra, the trumpeter swan issues a low, sonorous honk that's been likened to the sound of a French horn. Pairs often call in unison as they bob their necks simultaneously or brag about their success in driving off an intruder.
Nature probably painted the trumpeter white to camouflage it during winter, when the swans tend to gather in flocks. The bird's snowy plumage and elegant profile have made it something of an icon--whether depicted to sell cake flour or tenderly portrayed in E.B. White's classic children's book The Trumpet of the Swan.
Yet the trumpeter's beauty is no fiction. "It's one of the most awe-inspiring moments," Matteson says, recalling the bird's silhouette as it glides above a mist-shrouded lake. "You know you're seeing something early Native Americans and your ancestors have seen."
With the blessing of the U.S. Fish and Wildlife Service, biologists like Matteson and Johnson have collected the Alaskan eggs for their state programs selectively, always leaving at least two viable eggs in each nest.
Egg collection has not been easy. On Matteson's inaugural visit to the Alaskan nesting ground, for example, a male swan charged the back of his bush plane and snapped off the communications antenna; the pilot had to call his wife by ham radio and ask her to alert the airport tower that they were heading back. Johnson, who started making trips to Alaska in 1989, kept the precious eggs swaddled with hot-water bottles on the 18-hour journey back to Michigan. Once home, the biologist had to endure a nerve-wracking wait to see if the eggs would hatch. "I was more worried about those swans hatching than I was about the birth of my own kids. I watched them 24 hours a day," Johnson recalls.
But the trickiest part of the reintroduction program has been rearing the birds so they will remain wild. Each state has its own methods. One is "captive parent-rearing," where a flightless pair of trumpeter swans cares for the young until, at 10 months, they are removed and released. Another is "captive rearing," where the birds are placed in large pens after they hatch at zoos, then later moved to a pond and at the age of 23 months are taken to a remote wilderness area and released. Wisconsin has even used "decoy rearing," where University of Wisconsin interns hidden in a floating blind lure cygnets to follow an attached life-size adult trumpeter decoy.
Iowa has taken a much different approach. "We've capitalized on the enthusiasm of the public for our success," says Ron Andrews of Iowa's Department of Natural Resources (DNR). Andrews' program has formed 55 partnerships with "average citizens from all walks of life, in all corners of the state" to keep flightless breeding pairs of trumpeter swans in ponds on their properties. When young are produced, the cygnets are returned to the Iowa DNR for release in the wild. The program also uses the swan as a symbol to promote the importance of protecting wetland habitat.
A major question for wildlife managers has been whether and how the reintroduced swans would migrate. Midwestern trumpeters traditionally learned flight routes to prime wintering spots throughout the lower Mississippi Valley from their parents. Although the Alaskan stock was genetically "programmed" to migrate, scientists didn't know what the swans would do after being transplanted to the Midwest. They found that some birds didn't have to go far.
"We thought they had to migrate to be successful. That's proven not to be true," Johnson says. "It's a different world out there now. Sure, they used to migrate all the way down the Mississippi River to the Gulf of Mexico, but that was before nuclear power plants, coal-fired power plants, sewage treatment plants that discharge warm water and create habitat. Things don't freeze now like they used to--and these birds only go as far south as they need to to find open water and food."
Photo © GERARD FUEHRER
POACHED EGGS: Starting in the late 1980s, Midwestern biologists journeyed north each year to gently remove eggs from clutches in the large Alaskan trumpeter population. Nesting females (above) produce as many as nine eggs annually; scientists left at least two eggs in each clutch. Swaddled in hot water bottles, the eggs were flown back to the central states and hatched. Most cygnets were reared in captivity and released after about two years.
In addition to Wisconsin, Michigan and Iowa, the state-by-state effort to bring back the trumpeter swan includes Minnesota, Ohio, South Dakota and Nebraska, as well as the Canadian province of Ontario. Swan numbers in this region are now growing at a rate of 20 percent annually. The consensus among program managers, says Matteson, is that "we are well on our way toward establishing a self-sustaining population."
The trumpeter swan still faces challenges in the Midwest and elsewhere, however--mainly from ingesting spent lead shot, and from accidental or illegal shooting. Lack of genetic diversity is also a concern. "The native swan of the Midwest is gone," says Ruth Shea, director of The Trumpeter Swan Society, a nonprofit group based in Maple Plain, Minnesota. The 70 pairs in the greater Yellowstone area are the only original breeding population in the contiguous United States to survive, she notes. "The future of the species depends on the diversity of populations," Shea says.
But for the most part, biologists are celebrating the midwestern comeback of America's largest wildfowl and applying the lessons learned to other wildlife reintroduction efforts, such as the whooping crane in Wisconsin and the Nene goose in Hawaii. "It was an intellectual and scientific challenge to raise a bird in captivity that could be released in the wild and survive and reproduce," says Johnson.
Adds Andrews: "People were responsible for their demise, and I think people will be responsible for bringing them back."
Illinois writer Gayle Worland traveled to Michigan last summer to see captive-raised trumpeters for this article.
Safeguarding Migratory Birds
The trumpeter swan is among the many migratory bird species that are the focus of a new NWF initiative. "Because the migrations of birds do not acknowledge boundaries, our conservation efforts must extend from backyards to global collaboration," says Paul Joffe, director of NWF's International Affairs Program.