The White-tailed Ptarmigan is likely to be confused only with the other two ptarmigan species in B.C. It is the smallest of the three species, and can be reliable identified by its white tail (the tails of the other two species are black). The tail feathers are often hidden by the long uppertail coverts, however, which may necessitate attention to other plumage characteristics for accurate identification. The Willow Ptarmigan, which is found only in northern B.C. and along the Coast Mountains, is much larger and larger-billed than the White-tailed Ptarmigan and occurs at lower elevations (usually restricted to brushy areas at or below treeline). In early spring, males acquire a chestnut head, neck, and upper breast which contrasts sharply with the otherwise white plumage. Individuals in this plumage should be easily distinguished from White-tailed Ptarmigan. Later in the summer, the extensively chestnut or reddish-brown plumage of the male Willow Ptarmigan is similarly distinctive. Females are best distinguished from female White-tailed Ptarmigan by size and structural characteristics, as well as their noticeably richer rufous-buff plumage (extending onto the belly and undertail coverts). In winter, size, structure, and the black tail feathers should be sufficient to distinguish this species.
The somewhat smaller Rock Ptarmigan, which is still larger than the White-tailed Ptarmigan, occupies habitats that are intermediate in elevation between the other two species. Although it overlaps extensively with White-tailed Ptarmigan, it tends to avoid talus and rocky slopes in favor of mountain meadows and tundra. Males of all plumages have a dark line through the eye that immediately serves to distinguish them from White-tailed Ptarmigan; this feature is particularly prominent in winter plumage, as are the very large, bright red combs above the eyes. Breeding-plumaged males are much darker and browner on the head, neck, upper breast, and upperparts than male White-tailed Ptarmigan. Females are similar in structure to female White-tailed Ptarmigan, but are overall richer buff or rufous-buff in colouration (similar in tone to female Willow Ptarmigan). All plumages are immediately distinguished by the black tail feathers when these are visible.
| Displaying males produce a variety of calls during the breeding season, including a rapid, clucking pik pik pik pik piKEEA or duk-duk-duk-DAAK-duk-duk (given on the ground), a low, hoarse pwirrr, and a loud, four-syllable ku-ku-KIII-KIIER (given in flight); some courtship calls are very loud and can be heard as far as 1.5 km away. Both sexes give various clucking notes throughout the year, and these calls are sometimes interspersed among the male’s courtship calls. Also gives a high-pitched chirp when alert. Source: Braun et al. (1993); Sibley (2000); Madge and McGowan (2002) |
Courtship
Courtship displays begin in the spring (April-May) and are associated with the arrival of a female onto the male’s territory. Several courtship displays have been described, including the ‘Courtship Bow’, ‘Courtship Strut’, and ‘Courtship Chase’. During the ‘Courtship Bow’, the male approaches the female slowly while bowing the head in a rhythmic pecking motion. During the ‘Courtship Strut’, the male struts back and forth in front of the female, with his tail fanned, his wings drooped with the wingtips dragging on the ground, and the combs flared. During the ‘Courtship Chase’, the male slowly approaches the female with his head held upright, his combs flared, his tail feathers and undertail coverts held erect, his breast feathers fluffed, and his wings drooped. As the female moves away, he runs in pursuit of her while uttering a variety of clucking and cackling calls. Once the pair bond has been established, the male and female accompany each other almost continually prior to copulation (‘Mate Guarding’). A variety of loud, aggressive calls are given by both sexes (although more by the male) during this period in defense of the territory and mate. Pair bonds are retained for up to 3 years.
Nest
The female alone constructs the nest, which consists of little more than a shallow scrape on the ground (13-15 cm wide and 3-4 cm deep) that is lined with dried vegetation, moss, needles, and a few body feathers. The nest is typically situated in open, often rocky terrain or in brushy willow or krummholz vegetation and is usually at least partially concealed by overhead vegetation.
Eggs
A single clutch of (3) 4-7 (9) eggs are laid between mid-May and early July (variable, depending on latitude and local snow conditions) and is incubated by the female alone for 22-26 days before hatching. The smooth, slightly glossy eggs are pale buff to pinkish-buff with sparse but regular reddish-brown or dark brown speckling. Eggs are present in B.C. between mid-May and late July.
Young
The young are downy and fully precocial and leave the nest within 6-12 hours of hatching. The chicks are mottled with black, brown, buff, and cinnamon on the upperparts and are greyish-white to pale greyish-brown on the underparts (often with olive-brown mottling on the sides and breast). The crown and nape are reddish-brown with black mottling, the forehead is pale buff with black mottling, the throat and sides of the face are whitish or greyish-white, and there is a black streak behind the eye. The bill is black. The chicks follow closely behind the parents when young and are regularly brooded by the female, particularly during inclement weather. The young are able to feed themselves within one day of hatching and are not fed by the female (although she does direct them to sources of food). The young are able to fly weakly at ~10 days of age, and remain together as a family group throughout the first winter (dispersing in the following spring). Family groups that include young chicks have been observed in B.C. between late June and mid-September.
Source: Campbell et al. (1990b); Braun et al. (1993); Baicich and Harrison (1997); Madge and McGowan (2002)
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This species forages exclusively on the ground, where it picks food from the surface of the soil and rocks or browses on low shrubs and herbaceous vegetation. It consumes the buds, leaves, stems, seeds, fruits, catkins, and flowers of a wide variety of shrubs, grasses, and forbs, and also consumes insects during the breeding season. It shows a particular fondness for willow, and the winter diet is composed largely of willow buds; it also consumes the buds of birch and alder in areas where willow is absent. These buds are often available, even at the highest elevations, in windswept areas where the shrubby vegetation beneath the snow is exposed throughout the winter. Foraging birds occur singly or in pairs during the breeding season, but aggregate into small to medium-sized flocks of up to 35 individuals during the winter. When not foraging, winter flocks sometimes roost in burrows beneath the snow.
Source: Braun et al. (1993); Madge and McGowan (2002)
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