| Summary: | Between 15 August and 15 October 1991, 31 Newfoundland willow ptarmigan (Lagopus lagopus alleni) on the Fairhaven Barrens in Newfoundland, were fitted with poncho-style radio transmitters. Prescribed burns were conducted to remove caribou lichen (Cladonia spp.), a lichen that suppresses growth of the low sweet blueberry (Vaccinium angustifolium), the key food plant of ptarmigan. The 6800-ha study area has about 48% of the area in plots of prescribed burns ranging from 49 to 659 ha with a mean of 204 ha. The time since burning ranged from 1 to 3 years. Twenty-four birds were collared on the burn and 7 on the non-burn. In spring 1989, no statistical difference occurred in pair densities between the burn and the control (P=0.82); in spring 1992, densities were greater (P=0.09) in the burn (4.5 pairs/km2) than in the control (2. 7 pairs/km2). The percent cover of low sweet blueberry increased from 11 % in the non-burn to 37% in the burn (P<0.0001). The height of the vegetation increased from 12 to 21 cm (P<0.0001). No statistical differences were observed in home range size (P=0.49), covey size (P=0.37) or distances moved (P=0.41) between the burn and the control areas. A Chi-square analysis (P=0.15) showed birds collared in the burn selecting the burn and birds collared in the non-burn selecting the non-burn. Birds collared >300 m from edge (non-burn/burn) had 96% of their locations within the habitat in which they were collared. Birds collared <200 m from edge had only 65% of their locations in the habitat in which they were collared. Of all telemetry points, 76% were <350 m of the capture location. Although an area burned >/=2 years earlier provides better habitat for ptarmigan than a non-burn area does, birds in the burn <200 m from edge still used the non-burn habitat. Program Micromort indicates 47% survival for the fall, 53% for the winter, and 80% for the spring, with an estimated annual survival rate of 8%. Predation accounted for 78% of the mortality, with 67% traced to avian predation. Small mammal populations were low, with 1 capture in 1200 trap nights, suggesting predators were seeking alternate prey such as ptarmigan. Wildlife Habitat Canada and the Newfoundland and Labrador Wildlife Division
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