Corridors affect dispersal initiation in reintroduced peregrine falcons

Publisher Website
Google Scholar
Abstract
We reintroduced 33 peregrine falcons (Falco peregrinus) at two release areas with contrasting habitat configurations to assess landscape influences on dispersal. One site (Daniel Boone National Forest) had non‐forested corridors within a forest matrix, whereas the other site (Tom Dorman State Nature Preserve) had forested corridors within an agricultural matrix. We used aerial telemetry and ground observation to assess differences in dispersal between sites and we used multivariate statistical analyses to detect combinations of response variables depicting landscape influences. Non‐forested corridors at Daniel Boone affected post‐fledging movements and initiation of dispersal, whereas no discernable pattern in dispersal initiation was observed at Dorman Preserve. Results included significant (p<0.05) differences between peregrines at Daniel Boone and Dorman Preserve in x̄± SD post‐fledging area (PFA) size (2643.5±2599.0 and 931.7±732.1 ha, respectively), maximum movement distances (12.9±13.9 and 6.1±4.6 km, respectively), orientation of movements (second‐order x̄ angle±95% confidence interval (CI)=280.8±58.6 (non‐random orientation) and 358.8±98.8 (random orientation), respectively), time spent on the PFA (16.0±12.2 and 31.0±3.3 days, respectively) and selection of agricultural habitats (Euclidean distance vectors ρ=0.66 and ρ=2.50, respectively). Selection of agriculture by peregrines released on Daniel Boone reflected selection of corridors as part of pre‐dispersal movement. These results, coupled with generally unorientated movement behaviour by Dorman Preserve peregrines, provided evidence for an influence of functional landscape connectivity on dispersal in peregrines.