Gyrfalcons are the largest falcons in the world, and they’re year-long residents of Denali National Park. They eat arctic ground squirrels and ptarmigan, and occasionally on snowshoe hare. We saw this pair of gyrfalcons from the Denali Wonder Lake bus.
In this series the original photo shows the birds and distant mountains, and the two successive crops show the colors better. Like ptarmigan, gyrfalcons have feathers covering their upper legs, which helps them stay warmer in the winter. Click on the photos for enlargements.
This photo shows a gyrfalcon soaring over the valley.
See the tall boulder standing by itself in the valley. Our bus driver had previously hiked out to the boulder, which is 20 feet tall. The boulder is very large and heavy, and it’s standing by itself in the middle of a broad valley. “How did it get there?”, he asked.
A glacier carried it there. Once upon a time, glaciers covered the valley. The boulder fell onto a glacier. The glacier slowly moved downhill, carrying the boulder. When the glacier melted, the boulder was left alone on the valley floor. It’s called a glacial erratic.