Ptarmigans Molt With Season

Filed in Birding, Expert Articles by on November 12, 2013

TWG_story_birding13imgOne of the most difficult birds to find as a bird watcher is the white-tailed ptarmigan. This plump ground bird is more often stumbled across rather than “found” because it utilizes superb camouflage and holds perfectly still to keep it concealed. One usually discovers ptarmigans by nearly stepping on them. Imagine yourself enjoying a peaceful state of high altitude bliss, when suddenly you sense that the rocks are walking or that a snowball just blinked, this is how you find ptarmigans.

The camouflage of the ptarmigan is amazing. Ptarmigan molt to pure white in winter with only their black bills, eyes, and toes differentiating them from snowballs. As springtime nears, its plumage begins to change again with white feathers gradually replaced by black and brown feathers making it blend with rocks, shrubs and snow.

By summertime the molt is complete and its feathers are mottled black, brown, and tan and the ptarmigan is perfectly camouflaged among the lichen-covered rocks.

White-tailed ptarmigan spend their entire lives near or above treeline here in Colorado. The land on high peaks above treeline is known as the alpine tundra and supports many dwarf plants and flowers that are identical to the specialized plants found far north in the arctic tundra. Ptarmigans have adapted to these cold harsh climates and will be well designed to prosper throughout the next ice age.

Ptarmigans are related to grouse, turkeys and chickens. All of these birds spend most of their time on the ground walking. When flushed, there is quite a clatter of fast-flapping wings, and they usually burst from the ground then glide to a landing within fifty yards.

Ptarmigans grow thick feathers on their legs and toes for winter and their claws grow long. The result is increased surface area of their feet, so when walking on soft powder snow the feathered feet act as snowshoes keeping them afloat and making it far easier to walk.

Ptarmigan tracks are often seen in snow near the tips of willow branches where the ptarmigan browse on buds and twigs. These tracks can be perplexing because they seemingly begin and end out of nowhere. However, this clue tells us that the otherwise walking animal came in by flight. A closer inspection may reveal beautiful markings from wings that brushed the snow surface upon take off.

Ptarmigan scat to me looks like its been extruded, much like coarse-ground hamburger, but comprised of bits of vegetation. I’ve often found ptarmigan scat in little hollowed out snow caves below the snow surface. This suggests that like sled dogs of the far north, the ptarmigan uses the snow as an insulator from the howling winds and bitter cold temperatures.

Ptarmigans nest in early summer on open ground, usually near a boulder with vegetation concealing the nest site. The mother relies on her perfect camouflage to conceal her eggs and young from predators. She is completely committed to holding still and is reluctant flush because if she leaves the eggs, they will get cold and die. Upon hatching she nestles the young chicks beneath her belly to keep them warm and safe.

Like many other birds she starts with several chicks, but mortality rates are high and one-third of the chicks won’t make it through the first winter. Of the remaining young, about one-third won’t make it through the second winter. This demonstrates how winter separates the weak from the strong in the animal world.

Ptarmigans are preyed upon by air by goshawks and peregrine falcons. These raptors specialize in hunting other birds and are fast and maneuverable. By land ptarmigans are preyed upon by fox, coyote, and bobcats. These animals rely on keen senses of smell, hearing and vision to locate their prey.

Ptarmigans have adapted to cold arctic climates and do not ever leave this environment. We are blessed to have these beautiful birds as our neighbors here in Eagle County. Ptarmigans are the quiet guardians of our loftiest peaks.

Tom and Tanya Wiesen are owners of Trailwise Guides; a year-round Vail Valley guide service specializing in hiking, mountain biking, and natural history tours. Daily private tours are available. Contact Trailwise Guides at (970) 827-5363.

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