Ready For Takeoff

Though trumpeter swans once were considered one of the rarest birds in North America, they're fairly easy to spot in Yellowstone National Park. These two, along with a third, were somehow enjoying the Firehole River last week when the ambient air temperature was right around -21 degrees Fahrenheit (-29 Celsius).

This swan species is the largest of North American waterfowl, according to the Cornell Lab of Ornithology. In the wild they are thought to mate for life. And that can be a long time, as they can live to 24 years or longer.