The Beaver and the Swans

How de Havilland’s famous bushplane has helped protect a species.

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“Pair at two o’clock.”

Flying at 500 feet, pilot and biologist Bruce Conant looked in the direction I called and banked the

de Havilland Beaver toward the swans on the lake a mile away. We were flying as part of a month-long U.S. Fish and Wildlife Service project to study the Alaskan population of trumpeter swans before their annual migration south. Throughout last August, 14 aircraft flying up to eight hours a day would scour some 50,000 square miles of habitat, the largest attempt in the world, project managers believe, at an exact census of wildlife. Our job was to record the location of each sighting and tabulate the number of adults and young in every brood. With wildlife survey flight time in my logbook, I was on board as a volunteer observer.

A flyby of the swans on the lake yielded no sight of the young, called cygnets, whose tell-tale gray makes them hard to see from a distance. Using a knitting needle as a stylus, I input the pair of swans’ position on the touch-screen map, a digitized, GPS-linked version of U.S. Geological Survey maps we used to navigate and to record sightings. From the tabulation subscreen that appeared, I selected a “P” (for “pair”) and confirmed the entry. Had there been cygnets, I would have input their number.

We were flying into the Susitna Valley. On three sides of the lake, peaks of the Alaska Range rose, squeezing the northern end of the valley into nothingness, but Conant is a veteran of tight spots. After 30-plus years of bush flying, not much rattles him.

We were hoping for cygnets. Earlier discussions among observers had come to the dispiriting conclusion that many of the fledglings were undergrown, and probably wouldn’t be strong enough for the flight south. “You wonder what goes through the minds of those swans,” Conant said. “They must know the cygnets aren’t going to make it. I guess they don’t give up until the very end.”

Named for its call, the trumpeter swan, Cygnus buccinator, is one of the world’s largest flying birds, with weights up to 35 pounds and wingspans reaching eight feet. Once hunted for food and feather, by the turn of the last century they were thought extinct, victims of the slaughter of species that led to federal regulations to protect the nation’s wildlife. The Fish and Wildlife Service has monitored swan populations since the 1930s, when several dozen trumpeter swans were discovered in Yellowstone Park. In 1954 a population in the hundreds was found in southern Alaska.

Their size, magnificence, and brush with extinction have made trumpeters avian celebrities, and in addition to the protection of law, they enjoy the support of an organized advocacy group, the Trumpeter Swan Society. The society supports research into the sources of the lead that has poisoned thousands of the swans in the Northwest in recent years and pays close attention to the results of the aerial census, conducted every five years.

The swans’ anti-camo plumage is a great help to the census-takers. Occasionally a flash of brilliant white will warrant a closer look, usually to reveal itself as a bit of wind-whipped lake foam, sunlight reflecting off a rock, even a sun-bleached moose rack. But for the most part the adult swans are unmistakable and hard to miss, whether on a cobalt-blue alpine lake or nesting in the green reeds encircling a glacial pond.

The survey is alternately exhilarating and monotonous. In high-density areas, where it seems every one of the endless lakes has at least a pair, the project has the feel of a cattle roundup, as we cut and wheel one way, then another. But in some USGS quadrants, the terrain in the 15-mile square is unchanging and devoid of trumpeters, and an hour or two without a swan is enervating and mildly depressing, no matter how magnificent the scenery.

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