Home-Range Estimates of Red-Tailed Hawks Based on Random and Systematic Relocations

Abstract

We used 2 different relocation schedules to estimate home ranges of 4 radio-equipped red-tailed hawks (Buteo jamaicensis) in southeastern Colorado [USA]. From 8 September to 18 October 1986, each bird was relocated once a day, 5 days a week (random relocations) and tracked for 1 4-hour period/week (systematic relocations). Estimates of minimum convex polygons, 95% ellipses, 50% harmonic-mean activity areas, centers of activity, and observed range lengths based on relocations from random and systematic relocation schedules did not differ significantly from one another (all P''s > 0.05). Our results demonstrate the importance of understanding the effect of sampling stragegy on home-range estimation and indicate that biological and logistical considerations that result in autocorrelated data do not necessarily bias estimates of home ranges.