Northern Goshawk Home Ranges and Habitat Selection in the Great Basin of Southern Idaho

• Main Author: Hasselblad, Kristin Wood
• Format: Text
• Language: unknown
• Published: ScholarWorks 2004
• Subjects: Ornithology; Accipiter gentilis; Northern Goshawk
• Online Access: https://scholarworks.boisestate.edu/td/441; https://boisestate.on.worldcat.org/v2/oclc/61734078

CHAPTER 1: NORTHERN GOSHAWK HOME RANGE CHARACTERISTICS IN SOUTH CENTRAL IDAHO To measure northern goshawk (Accipiter gentilis) home range sizes and characteristics in south central Idaho, I radio-tracked six breeding males throughout the breeding seasons of 2001 and 2002. Males were tracked from the time young were 5-10 d old until 20 d post-fledging. I collected 485 temporally independent locations, 428 of which were triangulated, and 57 of which were obtained visually. I acquired a mean of 54 (± 3.3) independent locations per bird. Average linear error associated with triangulated locations was 130 m. Median minimum convex polygon home range size was 588 ha for males that successfully fledged young, and 542 ha for unsuccessful males. Median 85% cluster core area size was 98 ha for successful males, and 70 ha unsuccessful males. Home ranges contained an average of 1% seedling (< 2.5 cm dbh), 13% sapling/pole (2.6-12.9 cm dbh), 37% "small tree" (13-34 cm dbh) and 51% total forest cover and 49% shrubsteppe habitat. Core areas contained an average of 1% seedling, 11% sapling, 47% "small tree," 57% total forest cover, and 48% shrubsteppe habitat. These home ranges are smaller than those reported for elsewhere in North America. This may be due to high densities of hunting areas, which include areas of forest-shrubsteppe interface, where goshawks perch on forest edges to hunt open-country prey. Home ranges of both successful and unsuccessful males increased significantly in size after the mean fledging date of successful males' young. Home ranges of neighboring males overlapped. CHAPTER 2: NORTHERN GOSHAWK FORAGING HABIT AT SELECTION IN SOUTH CENTRAL IDAHO To assess northern goshawk (Accipiter gentilis) habitat selection at two scales in south central Idaho, I radio-tracked six breeding males throughout the breeding seasons of 2001 and 2002. Males were tracked from the time young were 5-10 d old until 20 d post-fledging. I collected 485 temporally independent locations, 428 of which were triangulated, and 57 of ...