They are among North America’s most numerous invasive birds. They’re glossy greenish ... tundra and trumpeter swans by its orange bill with a black knob. Introduced from Europe in the 1600s ...

Multicolored birds were developed over centuries of near domestication. Polytypic (12 ssp.; nominate in North ... iris orange to red; orbital skin blue-gray; bill grayish black; and feet dark ...

This species’ often confiding nature, distinctive plumage, pleasing song, and acceptance of human-dominated habitats make it one of the most beloved of North American birds. Polytypic.