Trumpeter Swans (Cygnus buccinator) are the largest of all North American waterfowl. Their melodic call has been missing from the eastern seaboard for nearly 180 years. Present throughout the continental United States, Alaska and much of Canada for tens of thousands of years, these majestic birds disappeared from many habitats soon after European colonization of the Americas.

Although the destruction of wetland habitat for conversion to agriculture played an important role in the disappearance of the species, indiscriminate hunting was the primary reason for decline. While killed for meat and skins, swans were mainly hunted for their feathers, which were used to make powder puffs, writing pens and to decorate women's hats. Swans and other migratory birds were not legally protected until 1918 with the passage of the Migratory Bird Treaty. But even with legal protection the species continued to decline -- by 1932 only 69 Trumpeter Swans were known to exist in the Lower 48 states.

To protect the few remaining Trumpeters, the U.S. government acquired over 13,000 acres in the Centennial Valley of southwest Montana in 1939. The chances for recovery improved in the 1950s when previously unknown flocks were discovered in parts of Alaska and Canada. Today a third population exists in the Midwest due to recent reintroductions of captive-bred birds and the relocation of wild individuals to Minnesota, South Dakota, Wisconsin and several other Midwestern states. Encouragingly, a continental survey of Trumpeters taken in 1990 found 15,630 individuals in the wild. In addition to reintroduction and relocation programs, the steady increase in numbers is directly attributable to the implementation of a variety of conservation efforts including establishment of refuges and sanctuaries, population surveys, federal and state land-use guidelines, and protection from shooting and lead poisoning.

Despite increases in all three populations, the species remains vulnerable. Reintroduction and relocation of Trumpeters, which have increased the overall populations, are not sufficient long-term conservation strategies because so far, reintroduced and relocated individuals lack the ability to effectively migrate to traditional wintering grounds. Although the instinct to migrate may remain, Trumpeters and many other species of birds must learn the historic routes of their ancestors from older generations of their species.

In addition, all three populations remain at risk from continued loss of wintering habitat and the concentration of wintering flocks at relatively few sites, both of which result in a high winter mortality. For these reasons several prominent trumpeter swan biologists have stated that the Rocky Mountain Population (RMP) may be at greater risk today than they were 25 years ago--even though their population has grown five-fold. Yellowstone's resident population, for example, share their high-altitude wintering habitat with virtually all the breeding Trumpeter Swans of Canada. The increasing numbers of wintering swans concentrated on this limited, harsh winter habitat makes them vulnerable to diseases, predation, and catastrophic losses. In addition, reduced flows during drought, heavy ice formation, unusually severe winter weather, or pollutants could destroy much of the RMP during a single winter. The Midwestern population of introduced birds is also at risk because no migrating flocks have become established and as this population increases, it is likely to encounter similar habitat use problems.