The first thing you are likely to notice in an encounter with a trumpeter swan is its size. This is a big bird, larger than any other species of waterfowl. Trumpeter swans can reach more than 25 pounds in weight. This requires broad, long and strong wings, of course. These sustain the trumpeter as one of the heaviest flying birds, though some terrestrial species, ostriches, for example, are heavier. Among North American birds, however, the trumpeter swan takes the prize.
Nor are wings and body mass the only out-sized features of this bird. The neck is improbably long and fairly thin. This contributes to the distinctive call that gives the bird its name. It is a noise you’ll notice, truly a kind of trumpeting.
Its great size and its pure white color made the trumpeter swan almost legendary, a kind of angel in feathers. That didn’t protect the birds from hunting pressure, however. Just the opposite was true. A trumpeter swan provided several pounds of meat, surely enough for a week’s rations for a family of homesteading pioneers. Swans weren’t hard to find; their dazzling color, their great size, their broad wings, their long necks and their calls attracted attention.
The consequence was a rapid and dramatic decline in the number of trumpeter swans. In “Breeding Birds of North Dakota,” Robert E. Stewart posits that these swans nested along the Missouri River and along larger lakes and streams in the eastern third of what became North Dakota. Meriwether Lewis noted the presence of very large swans in the spring of 1805, as the Voyage of Discovery was leaving Fort Mandan. Whether these were trumpeter swans is impossible to ascertain after more than two centuries, but they could have been.
The rival identification is tundra swan, a similar but smaller species. The two swans pose identification problems, but two points separate them. One of these is the call, which is more like a whistling noise in tundra swans. While it still evokes the wilderness, it lacks the kind of triumphalism of the trumpeter’s vocalization. The other clue is time of year. Tundra swans are migrants, moving from southeast to northwest in spring migration and reversing course in the fall. They are present in our area for several weeks in each season.
In either species, by far the most likely swan to be encountered is the tundra swan. In high summer, however, the trumpeter swan is the more likely by a wide margin. From mid-May to mid-October, any swan seen locally might be a trumpeter. Before or after those dates, tundra swans are far more abundant – though that doesn’t rule out seeing trumpeter swans.
The species can be differentiated in the field. Consult your field guide for details, which involve the size and shape of the bill, the presence or absence of a yellow spot in front of the eye, the shape of the bill itself, the thickness of the neck and the way the bird carries it.
Fine points, you understand.
How did this come to matter to birders in North Dakota?
As Brad Dokken’s story leading this section this week demonstrates, an extraordinary effort has brought the trumpeter swan back from the brink. The total population of trumpeter swans in the Lower 48 states was fewer than 200 only 50 years ago. Today, trumpeter swans “are doing extraordinarily well,” Mike Szymanski told me in answer to an email inquiry. Szymanski is supervisor of migratory game bird management for the North Dakota Game and Fish Department. He keeps track of waterfowl numbers. The population growth rate for trumpeter swans is “one of the highest long-term of any waterfowl species.”
“Increasingly we do get confirmed reports of broods in the northeast part of the state and up in the Turtle Mountains,” he wrote. The swans “seem to be increasing just about everywhere in the mid-continent.”
Last year, a pair of trumpeter swans spent some time on one of the ponds at Kellys Slough National Wildlife Refuge northwest of Grand Forks. They were the subject of a column in early fall last year – meaning that the trumpeter swan has been bird of the week twice in a year.
Szymanski pointed to success in Minnesota. “It’s interesting that trumpeter swans seem to be pretty good at finding wetland habitat restorations in western Minnesota. Maybe that’s a by-product of swan restoration efforts and where some birds are released, but nice to see nonetheless.”
Jacobs is a retired publisher and editor of the Herald. Reach him at firstname.lastname@example.org.