Two species of ptarmigan are found in Newfoundland and Labrador – the rock ptarmigan and the willow ptarmigan. They both have chunky bodies, short tails and legs, and short, rounded wings. They weigh from 0.5 to 0.8 kg. Sometimes called the “partridge”, they are the most popular game bird in the province.
In autumn, ptarmigan complete their moult to an almost completely white winter plumage. Both species have black tail feathers. The rock ptarmigan has a black stripe running from the bill to just behind the eye.
Their feet and toes are feathered, increasing their ability to walk in loose snow.
In spring, ptarmigan moult to a brown and yellow barred plumage. The rock ptarmigan has a more greyish brown head and chest compared to the reddish brown of the willow.
Ptarmigan inhabit treeline areas, arctic valleys, and tundra and barren upland. In autumn, they move to sheltered areas where willow, birch and alder buds will be available above the snow. The rock ptarmigan is found on the highest, most barren rocky ridges and hills, particularly along the coast and barren ground habitat.
Subtle differences in bill shape are related to the main winter food of each species. The willow ptarmigan, with a large, wide bill, feeds mostly on large willow buds and short sections of twigs. In Newfoundland, it subsists mostly on bilberry buds and twigs. The smaller, more slender bill of the rock ptarmigan is adapted to plucking the small buds and catkins of dwarf birch. Local names aptly describe the habitat preferences of the two species. On the south coast of Newfoundland willow ptarmigan are called “browsers” and rock ptarmigan ”rockers”. On the Labrador coast, they are called “brookers” and “barreners”, respectively.
The breeding season for ptarmigan is April to early May. In late May to early June, clutches of 3 to 14 eggs are hatched.
Because of naturally high winter mortality, fall and winter hunting seasons have little effect on the following year’s population level. Ptarmigan numbers also rise and fall in a 10 year cycle with population peaks at intervals of 8 to 11 years.