Juvenile Dispersal of White-Tailed Eagles in Western Scotland

• DOI: 10.3356/jrr-08-54.1
• Publication Date: 2009-06-04T17:01:48Z
• Authors: D. Philip Whitfield; Kevin Duffy; David R. A. McLeod; Richard J. Evans; Alison M. MacLennan; Robin Reid; David Sexton; Jeremy D. Wilson; Andrew Douse
• Keywords: 0106 biological sciences; 01 natural sciences

Abstract In long-lived raptors with delayed maturity, the period between fledging and settlement on a breeding site may take several years and is poorly understood. In our study of a reintroduced population of White-tailed Eagles (Haliaeetus albicilla), we investigated movements during this transient (juvenile dispersal) phase of natal dispersal using records of wing-tagged birds. Maximum juvenile dispersal distance (JDD), as measured from natal (or release) sites to locations recorded prior to birds settling on a breeding site ranged from 18 to 200 km in different individuals. Observation records suggested that (1) the most extensive movements occurred in the first two years after fledging, (2) males initially dispersed further than females, but, in their second year, females tended to be further from their natal site than males, and (3) as breeding age approached, males were closer to their natal sites than were females. Maximum JDD did not differ between wild-bred and released (reintroduced) birds and ...