Willow Ptarmigan (Lagopus lagopus)

[order] GALLIFORMES | [family] Phasianidae | [latin] Lagopus lagopus | [UK] Willow Ptarmigan | [FR] Lagopede des saules | [DE] Moorschneehuhn | [ES] Lagopodo escandinavo | [NL] Moerassneeuwhoen

Subspecies

Physical charateristics

Like ptarmigans willow grouse have feathered feet, unique among chickenlike birds, which improve their ability to walk in snow. They also have white wings throughout the year. Inflatable red combs above their eyes, which are especially evident in territorial and courting males, are inconspicuous to barely visible in females. Willow Grouse cocks, or males, have distinctive rufous chestnut heads, necks, and chests, whereas the remainder of their bodies is white. When the moult is completed in summer, the entire bird, except for the lower abdomen and wings, is chestnut brown. During their first two to three weeks of life, ptarmigan chicks have a downy plumage of intricate yellow, brown, grey, and chestnut patterns. They then assume a brownish juvenile plumage, not unlike that of females, which is retained until fall, when it is replaced by the typical white winter plumage.

Range

North America, Eurasia : North

Habitat

In summer, Willow Ptarmigans inhabit treeline areas, arctic valleys, and coastal tundra where vegetation is relatively lush and tall. They like moist areas, such as pond edges, streamside thickets, and marshy tundra, which they sometimes share with waterfowl and shorebirds. Recently, Willow Ptarmigans have been extending their range northward into parts of the Arctic formerly inhabited only by Rock Ptarmigans.

Reproduction

Male Willow Ptarmigans, the only family-conscious fathers of the grouse group, are an exception. They guard their mates closely throughout incubation and habitually help in rearing the young.
Although all chicks usually hatch within a few hours, hatching may take as long as a day. During this time, the hen keeps the brood warm, but the youngsters emerge from under her breast for short periods. Then, while making low vocalizations, the hen leads the chicks, each weighing about 15 g, from the nest. At first the family hunts for food in the vicinity of the nest, but it then ranges over an increasingly large area and can travel considerable distances in search of suitable food.

Feeding habits

Grouse mostly plant eaters. In summer, they sample the leaves, buds, catkins, flowers, seed capsules, bulblets, and berries of a wide variety of tundra plants. They also consume mosses and supplement their menu with insects and spiders when these are available. They have an uncanny knack of choosing the most nutritious material available, a necessity for meeting their high energy demands.

Chicks need a high-protein diet for rapid growth. After eating the yolk sac from which they hatched, they begin to pick up a variety of objects, especially caterpillar, other invertebrates, flowers, and seeds.

Winter is the critical time, as the choice and quantity of food are reduced to the few plants found above the snow or in windswept places. Ptarmigans eat the seeds, buds, and twigs of low willows, alders, and dwarf birches. To consume the catkins and buds of other trees and shrubs, Willow Grouse have learned to perch, somewhat unsteadily, in thin branches

Conservation

This species has an extremely large range, and hence does not approach the thresholds for Vulnerable under the range size criterion (Extent of Occurrence <20,000 km2 combined with a declining or fluctuating range size, habitat extent/quality, or population size and a small number of locations or severe fragmentation). Despite the fact that the population trend appears to be decreasing, the decline is not believed to be sufficiently rapid to approach the thresholds for Vulnerable under the population trend criterion (>30% decline over ten years or three generations). The population size is extremely large, and hence does not approach the thresholds for Vulnerable under the population size criterion (<10,000 mature individuals with a continuing decline estimated to be >10% in ten years or three generations, or with a specified population structure). For these reasons the species is evaluated as Least Concern.
The range of the rock ptarmigan is circumpolar. Its territory spreads in a circle around the arctic. In North America it can be found in Alaska and northern Canada. It is also found in Scandinavia, Russia, Finland, Greenland.
Lagopus lagopus is a widespread resident across much of northern Europe, which accounts for less than half of its global range. Its European breeding population is
very large (>2,100,000 pairs), and was stable between 1970-1990. Although there were declines in the United Kingdom and Finland during 1990-2000, other significant
populations in Norway, Sweden and Russia were stable or fluctuating, and the species remained broadly stable overall

Migration

Resident, except on Russian tundra where apparently partially migratory (see Distribution). In Scotland, males almost entirely sedentary and females mostly so, few moving more than 5 km. Establishment of territories and pairing occur late autumn; surplus birds failing to obtain territories to some extent transient, also visiting woods and fields up to 5 km from moor; by January-February driven off moor, and forced into marginal areas where they soon die; surplus males do not colonize distant areas.
Scandinavian populations of Willow Grouse also mainly resident, but in flocks all winter until territories established early spring and dispersal takes place, with movements up to 10 km or longer. Along coast of Norway, leaves smaller islands in September for larger islands or mainland, returning March-April, though movements seldom over 20 km

Distribution map