The Trumpeter Swan (Cygnus buccinator) feed while swimming, sometimes up-ending or dabbling to reach submerged food. The diet is almost entirely aquatic plants. In winter, they may also eat grasses and grains in fields. The young are fed on insects and small crustaceans along with plants at first, changing to a vegetation-based diet over the first few months. Predators of Trumpeter Swan eggs include ravens, raccoons, wolverines, black bears, grizzly bears, coyotes, wolves, and river otter....
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The Trumpeter Swan (Cygnus buccinator) feed while swimming, sometimes up-ending or dabbling to reach submerged food. The diet is almost entirely aquatic plants. In winter, they may also eat grasses and grains in fields. The young are fed on insects and small crustaceans along with plants at first, changing to a vegetation-based diet over the first few months. Predators of Trumpeter Swan eggs include ravens, raccoons, wolverines, black bears, grizzly bears, coyotes, wolves, and river otter. Madison River, Yellowstone.
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