Trumpeter swan
North America's largest waterfowl, a white swan with a trumpeting call, found on rivers and lakes from Yellowstone to the Dakota prairies.
Trumpeter swan at a glance
Cygnus buccinator TRUM-puh-tur swahn; Cygnus buccinator is SIG-nus buk-sin-AY-tor
- Type
- Bird · waterfowl
- Diet
- Herbivore
- Size
- Adults weigh 20 to 30 pounds, about as heavy as a large bag of dog food, with wings that open wider than a pool table is long: up to 8 feet across.
- Lifespan
- Up to about 25 years in the wild; a banded bird in Wisconsin lived 26 years and 2 months.
- Conservation
- Least concern
Eats pondweed, sedges, wild rice, aquatic insects (cygnets only)
Adults tip forward in shallow water to reach the roots and leaves of pondweed and other aquatic plants, eating up to 20 pounds of vegetation a day. Cygnets eat mostly aquatic insects and crustaceans for their first few weeks.
Should you worry?
Trumpeter swans are not a danger, but give a nesting pair room. An adult defending a nest or cygnets will hiss and can strike hard with its wings, so watch from a distance and never approach a swan with young.
Seventy-two adult trumpeter swans. That was the whole resident population on Yellowstone’s rivers and lakes in 1961, a hard-won number after market hunters and vanishing wetlands had nearly erased the bird from the Lower 48 by 1930. A swan gliding across a quiet bend of the river today still looks like plenty: pure white, neck held in a long curve, big enough that a mallard paddling beside it looks like a toy.
That 1961 number did not hold. After a winter feeding program at Red Rock Lakes ended and its winter ponds were drained in the early 1990s, the park’s resident swans kept losing ground to predation, human disturbance, and wetlands shrunk by drought and warmer years. By 2009 the count was 4 adults, the lowest on record. The park’s swans had come close to vanishing a second time, and this time no hunter was involved.
The count has climbed back since: 26 adults and 5 breeding pairs by 2023, still a fraction of the 1961 peak and still checked every spring by park biologists working the same handful of nesting territories. See a swan pair with cygnets on a Yellowstone pond this summer, and you are looking at one of only a few families in the whole park.
Did you know?
- Yellowstone's trumpeter swans dropped from a peak of 72 birds in 1961 to just 4 adults in 2009, the lowest count on record for the park.
- An adult trumpeter swan eats up to 20 pounds of leafy aquatic plants a day, tipping forward in the shallows to reach roots and stems most other birds cannot.
- A trumpeter swan's wingspan can reach 8 feet, one of the widest of any North American bird.
Common questions
How big is a trumpeter swan?
It is North America's largest waterfowl, weighing 20 to 30 pounds with a wingspan that can reach 8 feet.
Are trumpeter swans dangerous?
Not usually, but a parent guarding cygnets will hiss and can strike with its wings, so keep your distance from a nesting pair.
Why are trumpeter swans rare at Yellowstone?
The park's resident population crashed from 72 birds in 1961 to just 4 adults in 2009 after a nearby winter feeding program ended, plus predation, human disturbance, and drought-shrunk wetlands. It is still recovering.
What do trumpeter swans eat?
Mostly pondweed, sedges, and other underwater plants, which they reach by tipping forward in shallow water like a much bigger duck.
What eats a trumpeter swan?
Bears, wolves, coyotes, wolverines, raccoons, and ravens take eggs from the ground nests. Coyotes, bobcats, foxes, and golden eagles hunt young and adult swans. People have killed more of them than anything else.