Trumpeter Swans
Season of the cygnets
For the past few months, I have been watching a nesting pair of Trumpeter Swans that frequent a pond south of St. Cloud that happens to be on my commute to work. In March, they chose the large open water wetland to nest in. I have noticed that this particular pond has played host to nesting swans for the past four years. It is likely that this same pair has been returning year after year.
Having arrived well before the ice was out; the swans patiently waited for the warming air to open the icy seal covering their home. When not swimming in the small open area in the center of the pond, they would sleep on the ice with their heads tucked under their wings, often standing on one leg with the other drawn up close to their bodies.
The ice receded day by day, and finally the shoreline was exposed. They built a nest of vegetation and feathers on top of an old muskrat house, a process that took them approximately two weeks.
It was difficult to monitor their progress, as the nest was far away from the road. I could see the adults, but I was too far away to see if there were babies. Finally, one morning I saw the whole family closer to the road. Five young had fledged. The young, called "cygnets", were light gray in color and will remain so until their second year.
The first time I ever saw these magnificent birds was on a solo camping trip to Yellowstone National Park in 1978. Fascinated by their beauty, I watched them through my spotting scope for nearly four hours. At that time, they were quite rare.
The largest species of North American waterfowl, Trumpeter Swans were common prior to the arrival of Europeans. Greatly prized for their skins and feathers, Trumpeters were hunted to near extinction, and often affected by lead poisoning from lost and discarded fishing sinkers and lead shot. In 1935, only 69 individuals were left in the wild. Nearly half that population was located in the Greater Yellowstone area near the park. This region is famous for its hot springs which kept the water open year round, providing the essential food and cover that the swans needed. The Red Rock Lakes National Wildlife Refuge was established to provide full protection to this magnificent bird.
Efforts were made in other areas to preserve and restore habitat. This led to a rebound their numbers, and the current population is nearly 16,000 in the United States. I now see them regularly in many locations around the St. Cloud and Maple Lake area.
With their white rumps pointing comically skyward, swans use their long necks to reach down to the mud and sediments below, searching with their bill to find food. Trumpeter swans feed on leaves, the seeds and roots of aquatic vegetation, insects, and crustaceans. Their most important foods are duck potato and sago pondweed. In shallower waters, the swans will use their large, webbed feet to dig through the pond or lake bottom for roots, shoots, and tubers, and then plunge their heads and necks underwater to eat what they've dug up. Their webbed feet are of course useful for swimming as well. Swans may look as though they gracefully and effortlessly float upon the water, but beneath the surface, their feet are frantically paddling away in order to get anywhere at all. A swans’ beautiful white plumage often can become stained with a rusty color from the iron in the waters they swim upon.
Changing from a cygnet to a white plumage is a sign of reproductive maturity. Once two swans have formed a pair bond, they often mate for life. The male swan, called a cob, brings nesting materials to the female, called a pen. She places the material upon other vegetation until the nest is 6 to 12 feet in diameter. She lays 4-6 eggs, which are considered precocial, as the young are ready to leave the nest very soon after hatching- unlike backyard songbirds who may take weeks. After raising their young, the swans make a partial migration, staying wherever they can find open water. They can live up to 24 years, migrating back and forth to their breeding grounds through their years, gracing us with their presence in the summer months while they raise their young on lakes and ponds like the one south of St. Cloud where this family can often be seen.
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