Willow Ptarmigans in Denali

I traveled to Alaska to see Alaska's land and wildlife and my wish list was so long, every encounter held something magical for me.  Seeing a group of Willow Ptarmigans (Lagopus lagopus) under shrubby willows growing along side a stream on our disco hike gave me exceptional delight.  

Thanks to Ranger Bob, who alerted us to their presence so we wouldn't march right up to them, we were able to get some good looks before our hiking group was ready to push on and cross the stream.  I was lucky enough to have a second encounter two days later near the road and in a vehicle that made a perfect blind for these close-ups images.

The Willow Ptarmigan is the largest and most numerous of the North American ptarmigan.  It makes its home in arctic tundra and alpine habitat during the summer months, liking moist tundra with low shrubs of willow and dwarf birch.  The willow subspecies molts almost continuously from spring until late fall, changing its appearance as the season's foliage changes. 

The plumage of both sexes is entirely white in the winter.  In the spring the male acquires a rufous head and neck with the body remaining white during the breeding season, and during the summer the body is brown, with the wing and belly remaining white and the tail black.  As fall advances, the rich rufous brown becomes more grayish to match color changes in the tundra and gradually as the season progresses into winter, more and more white appears.  Clearly camouflage is a key survival strategy for this ground dwelling species.

In the image above you get a nice look at the white wing as this bird stretches.  Also notice the black tail feathers and the feathered legs and feet.  The feathers on the toes serve two functions:  insulating the toes for warmth and reducing heat loss, and providing a larger surface that acts like snowshoes to facilitate walking on top of snow.

The toe nails/claws grow longer in the winter and have the special function of digging through snow.  One of the ptarmigan's arctic and alpine adaptations includes roosting in burrows during the night.  I read two descriptions of how this is done.  In one method, the bird lands on a soft, deep snow bank and digs a burrow for cover.  In the other method, the bird flies toward the snow surface, folds its wings and plunges through.  Once under the surface, the bird moves forward horizontally several body lengths and often causes the "tunnel" to collapse creating a cozy chamber.  The "ptarmigan warms its own surroundings to near the bottom of its thermoneutral zone, the range of temperatures where it does not have to shiver." (Ronald L. Smith, Interior and Northern Alaska:  A Natural History)

A good view of the black tail above and the darker grayish feathers on the back.  This was the plumage stage in early September.  In the summer months Willow Ptarmigan eat the fruits of blueberries, cranberries and crowberries, and the leaves of willows and blueberries, plus a variety of insects.  In the winter the buds and twigs of willows make up 80% of their diet.

Be sure and take a look at the Willow Ptarmigan link below showing plumage stages and, as you scroll down the page, a video of a family of ptarmigan.  The male Willow Ptarmigan stays with the female and young throughout the breeding season and acts as a guard to protect the family.

This is the second post in a series about my Discovery Hike in Denali National Park and Preserve, Alaska, lead by Denai Ranger, Bob King.  To see the first post click here.
Next:  More hiking discoveries in the tundra

Links and Resources:
Click this link to view all my posts on Denali National Park and Preserve.  To see all posts on my visit to Alaska in the fall of 2012, visit Alaska

Denali National Park and Preserve
Willow Ptarmigan
Alaska wild berries
bog blueberries