Home-range size of northern flickers (Colaptes auratus) in relation to habitat and parental attributes

Energetic requirements during the breeding season and environmental factors such as food abundance and habitat quality may influence spatial use of the landscape by adult birds. We determined home-range and core-area sizes for 52 adult northern flickers (Colaptes auratus) during the brood-rearing period in 1999 and 2000 in British Columbia. We examined the relationship between home-range size and correlates of energetic demands (age, sex, body size, brood size, nest density, laying attempt). We also examined the association between vegetation type at the landscape scale and ground-cover characteristics at the foraging scale with home-range size, core-area size, and maximum distance flown from the nest to forage. Mean home-range size was 25 ha, with a mean core area of 7 ha. Home-range size was positively related to laying attempt and nearest neighbour distance. No significant relationships were found at the landscape level between vegetation type and home-range size or between ground-cover characteristics and core-area size. However, flickers flew farther to forage in home ranges with tall vegetation and bare ground. Home-range size of flickers may be related to both energetic demands on the adults and on the spatial arrangement of quality foraging patches around the nest site.