By Mary Nelesen
For the past five summers, I have searched in vain for a glimpse of a White-tailed Ptarmigan. This past summer, I was fortunate and saw a flock of them just by chance. Myfirst experience in seeing this elusive bird was while walking along the Highline Trail at Logan Pass in Glacier National Park. Two friends and I decided to stop and eat our lunch just below Haystack Butte. As we approached a large flat rock to sit on, we noticed four small speckled-brown birds nearby. Sure enough, there were 3 young and an adult Whitetailed Ptarmigan. We sat for nearly an hour just watching them and during all that time, they did not appear disturbed by our presence. They were feeding on plants/flowers and although several hikers walked by inclose proximity to where they were feeding, the Ptarmigan did not retreat or fly away.
The white-tailed ptarmigan is the only ptarmigan species found south of Canada. It is the smallest member of the grouse family in North America, averaging about a foot in length and weighing less than a pound. Unlike North America’s other two ptarmigan species, the white-tailed ptarmigan has a white tail year round,thus its scientific name. The white-tailed ptarmigan is a mottled gray brown in the summer with a whitetail, underside, and wings. In the fall, both sexes turn reddish-brown before white feathers begin to replace the darker ones. By early winter, males and females are all white except for a black bill and eyes. The white-tailed ptarmigan lives year-round in the alpine tundra, above the tree line, in rocky areas and meadows/snowfields. It is the only bird in the alpine zone to remain there during winter, instead of migrating. It has feathers around its nostrils so the air that it breathes in is warm before it reaches its body. The white feathers help camouflage it and its feathered legs and feet act as snow shoes.
A Species of Special Concern in Montana, the white-tailed ptarmigan are well adapted to the cold but are intolerant of high temperatures. The stunning white phase may ultimately be the White-tailed Ptarmigan’s demise with current warming projections. The signal to change plumage is triggered by photo period (the period of daily illumination a plant or animal receives), not temperature. The ptarmigan, like the pika, are stressed by warm temperatures above 70 degrees and may take snow baths to cool themselves down.
According to researcher Dr. David Benson, Associate Professor of Biology at Marian University, who has conducted a 13-year study examining White-tailed Ptarmigan changes in distribution, habitat and numbers in Glacier National Park, the White-tailed Ptarmigan are not well adapted to hot summer temperatures.His study found Ptarmigan flocks are presently smaller and less numerous than described in ’96 and ’97.“White-tailed Ptarmigan in Glacier National Park appear to be changing distribution, changing habitat, and perhaps on a local scale, declining.” The following graph supports his research.
Table 1: Flocking individuals and flock sizes from 1959 (Choate 1963a), 1997 (Benson 1999), and2009. 1959 and 1997 individuals were individually marked. “Big day” indicates the number of flocks and total birds seen on one day of searching the Logan Pass study area. As you can see by the chart, I was indeed fortunate to come across one of the few remaining White-tailed Ptarmigan flocks at Logan Pass last summer.
As a footnote, Dr. Benson recently told me he found 6 territorial males in the Logan Pass area this past summer (2010) in June, which is about the same as what he was finding back in the early 90’s. In other words, while late summer numbers are declining, there is less evidence that breeding numbers are going down on Logan Pass.
|Total Flocking Individuals||55||18||10 (unmarked est.)|
|“Big day” on Logan Pass||4 flocks, 33 birds||2 flocks, 12 birds||3 flocks, 7 birds|
Montana Outdoors Magazine, 2003-2006
Benson: Ptarmigan 2009, unpublished draft
Benson, David and Matthew Cummins, School of Mathematics and Sciences, Marian
University, Indianapolis, IN, USA. “Move, Adapt or Die, a 13-year comparison examining White-tailed Ptarmiganchanges in distribution, habitat and number”
The Audubon Society Encyclopedia of North American Birds, John K. Terres