Ptarmigan: A good lifeform comparison of similar habitats
By Dave Hanks
The following is a biological rule: When starting at sea level and then ascending a tall mountain, the vegetative types will change in the same manner as if you were to travel from the equator to the polar icecap. The lower elevations have very tall trees. As you ascend, the trees become shorter with an increasing amount of conifers. Just before the alpine zone (or Tundra), the trees are small & stunted. The landscape then becomes grass, with low growing shrubs, and finally snow and ice.
It is no wonder that animal specie types tend to mimic this rule. The Ptarmigan is an example of how species can be similar in similar habitats. The White-Tailed Ptarmigan lives in the tops of our Rocky Mountains, while the Willow and Rock Ptarmigan inhabit the far northern Tundra. All these Ptarmigan live in a “chilly” habitat, and all undergo a change from a camouflaging brown in summer to white in winter.
The Willow Ptarmigan male is distinguished by his red eyebrow. This 14 to 17 inch bird’s diet consists of leaves, shoots, berries, seeds, and insects. Their scat is very un-scat-like, resembling small woody pellets. They have a most distinct call. It’s a rapid, nasal chucking in descending sequence. The sound has good carrying volume and is unforgettable.
Hawks, owls, and fox are their main predators. Because they are slow fliers, they do best remaining on the ground, using their camouflage, when encountering an enemy from above. This state Bird of Alaska is a “Jekyll/Hyde.” It changes from a highly camouflaged, barred, rust color in summer to pure white in winter.
There is an interesting town in east-central Alaska named Chicken, Alaska. It was named for the abundance of Ptarmigan in its locale. The difficulty in the spelling of the species name caused the residents to settle on Chicken. After all, it is a chicken-like bird. The accompanying photograph was obtained in Denali National Park. This male was feeling secure in the stunted Willows that line the park’s Savage River.
(A male Willow Ptarmigan undergoing a color change)
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