Trumpeter Swans

Written by Gretchen Walker

Dark shadows stretched across the still lake as the trumpeter swans floated across the reflection of Mt. McKinley. Some of the big white birds’ tails tipped up as they searched beneath the water for the tender parts of aquatic plants to eat. Other swans slept with their heads tucked against their wings. Those swans still awake combed their sleek feathers with long black bills.

Occasionally a loud brassy call echoed through the quiet evening. The thick birch trees of the Alaskan forest were beginning to turn yellow as autumn approached. The swans were gathering together for the southward migration.

Crouching in the bushes on the shore, Mary Anne, my four-year-old daughter, and I studied the big graceful birds. Most were gleaming white, but five were a dusty gray color that marked them as cygnets, swans less than a year old. These five all belonged to one pair of adult swans. Most other kinds of birds we had seen raised many more babies than this, so we wondered why only one pair of swans out of the whole flock succeeded in raising a family.

Trumpeter swans are still considered an endangered species, although their near relatives, the whistling swans, are found in considerably greater numbers. When white men first came to North America, trumpeter swans were common in all of the north, west, and central parts of the continent. As men moved into the swans’ territory, they killed the birds for their fine white feathers, which were used to adorn ladies’ hats, and for their soft swanskins.

By the 1930s there were fewer than a hundred trumpeter swans. In 1935 the first refuge designed to save the swans was established at Red Rock Lakes in Montana. Of all the efforts made to save a critically endangered species, the Red Rock Lakes Refuge has been one of the most successful. The number of trumpeter swans is now increasing, and hundreds of these elegant birds have moved back into their old territory.

Swans mate between the ages of four and six, and they remain with their partners for life. Both the pen (female) and the cob (male) help raise the cygnets. Scientists have found that swans will not nest and try to raise a family unless they have a medium-size lake, or at least several hundred acres of a larger lake, mostly to themselves. Those that do find a suitable unoccupied area build large nests of grass on a lump of earth or on a muskrat house surrounded by water. The pen lays three to nine eggs in the nest.

As many as half the eggs may fail to hatch after the thirty-three-day incubation period. Biologists feel that many eggs are infertile. However, from watching swans at our home in south-central Alaska, we learned that sometimes heavy rains or new beaver dams raise the water level until the nests flood and the eggs get too cold to hatch.

We also noted that one particular pair of swans was away from their nest for up to thirty-six hours. Before they left, they covered their nest with a mat of grass about four inches thick to help keep the eggs warm. But the eggs were still unprotected against predators and rain. Perhaps these swans were just young and inexperienced, but their eggs never hatched.

The swans that nested near our home were curious about our activities, and they showed little fear of my daughter and me. They came quite close when we imitated their calls, and they often followed us when we walked along the shore. Even Mary Anne’s squeaky version of a swan’s trumpeting drew quick replies from the great white birds.

One spring many freshwater mussels that had been killed by an unusually cold winter were floating in our lake. The swans ate the mussels, although they are not generally thought of as meat eaters, along with their usual fare of plants such as sedge grass and water milfoil.

One day we watched a swan sneak up on its neighbor, which was tipped up feeding, and bite it on the rump. The bitten swan came up squawking and flapping and chased the jokester away. All was peaceful until another bird nipped a neighbor and the lake was again filled with splashing and loud squawks.

Each mated pair stayed close together even when feeding in the flock. They would sometimes face each other, rear back on their tail feathers, and beat the water with their wings. Then they would settle back down and bob their heads in unison, looking like mirror reflections of each other. This was a typical courting display between swans preparing to mate, but we saw them doing this in the fall, too, when courting season was long over. Only mated pairs seemed to behave toward each other in this fashion.

Members of different flocks did not mix, and any outsider that tried to socialize was chased back to its own group. The pair of swans with the five cygnets even kept a little distance from their own flock in order to guard their young—although the gray cygnets were now the size of adults. Two single swans stayed nearby and chased intruders even more vigorously than the parents themselves.

We have much to learn about swans before we can fully understand how they live, why they have such poor success reproducing, and what we can do to help them. Certainly two of the most important problems facing waterfowl are the destruction of marshlands by the damming of rivers and the draining of swamps and the pollution of waterways.

The trumpeter swan has made an outstanding recovery from near-extinction, but much more needs to be done before these great birds can be considered truly safe.

Photographed by Gretchen Walker