Swans

Winter Swans

Tundra Swans

Tundra Swans

Text and photos by Dan Gleason © 2008

Those of you who live in rural portions of Lane county may now be witnessing the arrival of swans, returning to spend the winter here in the Willamette Valley. Each winter, several thousand Tundra Swans venture here, at the end of their southward journey from breeding grounds on the Arctic Tundra. Occasionally, a few of the much rarer Trumpeter Swans are found mixed with the more common Tundra Swans. During their migration flights, swans fly nearly 50 mph, at altitudes of 3,000-5,000 ft. and some have been reported at nearly 10,000 feet. Shorter flights between resting and feeding areas, however, are seldom higher than 800 ft.

Throughout history, swans have been revered in legend and mythology and supernatural powers have often been attributed to them. In ancient Greece, it was believed that a swan would only sing just before it died, an idea that led to our expression “Swan Song.” Today, we no longer attribute special powers to these birds but we still consider them symbols of grace and beauty and take special pleasure in viewing them.

There are 7 species of swans in the world. Two are native to North America: The Tundra Swan (formerly known as Whistling Swan) and the Trumpeter Swan. Wild Whooper Swans (from Asia) are found on some Aleutian Islands and occasionally farther south into our western states. The Mute Swan from Europe has been widely introduced and some feral populations now exist, and the Black Swan from Australia has become increasingly popular as an introduced “ornamental” bird.

Swans are the largest of all waterfowl, weighing more than 20 pounds. Some male Trumpeter Swans have been known to weigh over 27 pounds, making them one of the heaviest of all flying birds. The more common Tundra Swan seldom weighs more than 21 pounds, but that is still quite heavy for a flying bird. The plumage of most swans is all white with the exception of the Black Swan of Australia, the Black-necked Swan of South America, and the Coscoroba Swan of South America which has black wing tips.

Some of the highest feather counts of any bird were obtained from swans. More than 25,000 feathers were counted on an individual Tundra Swan and 20,000 of those (80%) were found on the head and neck. (Imagine the tedious process of hand-counting those feather!) By contrast, most songbirds have between 2,000 and 4,000 feathers covering their bodies.

As with many birds, a swan’s first year is its most perilous. About half of the birds hatched each year will not survive to be one year of age. For those that do survive their first year, their chances of a long life are very high. It is not known how long swans can live in the wild, although one Tundra Swan was recaptured 21 years after it was first banded and a Trumpeter Swan is known to have survived at least 23 years.

During their long lives, swans stay together as monogamous pairs. Birds begin to form these pairs at about 2-3 years of age but breeding does not occur until the year after the pair-bond is formed. Once established, a pair-bond is maintained throughout the year and individuals remain together throughout their lives. Only rarely do paired birds go their separate ways. Before the bond forms, individuals may pair temporarily with other immature birds, even individuals of the same sex, but such pairings are short-lived.

Family units are important to swans and first-year birds will remain with their parents throughout the winter. Migrating flocks consist of several families traveling together, and when they leave our area in the spring, the immature birds follow their parents back to the Arctic. As they reach the breeding grounds, the young will finally break away from their parents to begin life on their own. They will not seek a mate until at least the next year or even two years later.

In recent years, swans have sometimes come in conflict with the needs of farmers whose fields are used as foraging sites during the winter. Historically, the primary diet of swans was aquatic vegetation and a few aquatic invertebrates as well as seeds, stems, or other parts of aquatic and wetland plants. Much of the habitat once used by migrating swans has been converted to agricultural or other human usage, making historic food resources and habitat no longer available. As a result, many swans now feed in grain fields where they have the potential for creating problems.

While on their breeding grounds in the Arctic, swans spend nearly all of their time at or near the nest site. While here in the winter, swans go back and forth between fields, where they feed during the day, and open water, where they spend the night. Most of our wintering swans spend the night on Fern Ridge Reservoir, leaving shortly after dawn to feed in nearby fields.

Since they are a large bird, they have few enemies. Habitat destruction and hunting, allowed in some states, are the leading causes of death. While in the Arctic, wolves and bears sometimes take swans, and the young birds and eggs are also at risk from Golden Eagles, gulls, and jaegers. In general, adult birds have little to fear and if attacked, are capable of defending themselves quite vigorously.

To find swans to view, search along many of the open fields such as those surrounding the airport. It can also be an impressive spectacle to watch as these birds lift off of the reservoir very early each morning. They will fly low overhead so that you not only see them, but can hear the whoosh of their wings and hear their trumpeting calls. It the weather is clear, this usually happens at dawn, but be aware that during our winter weather, early morning fog is often present. On such mornings, the swans may wait a little longer before leaving or fly through and above the fog, allowing you to hear but not see these magnificent birds.

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