Individual study: Survival and breeding success of translocated white-tailed eagles Haliaeetus albicilla reintroduced into western Scotland
Evans R.J., Wilson J.D., Amar A., Douse A., MacLennan A., Ratcliffe N. & Whitfield D.P. (2009) Growth and demography of a re-introduced population of white-tailed eagles Haliaeetus albicilla. Ibis, 151, 244-254
This study is summarised as evidence for the intervention(s) shown on the right. The icon shows which synopsis it is relevant to.
A 2009 review of two white-tailed eagle Haliaeetus albicilla translocation programmes in western Scotland (Evans et al. 2009) found that the release of 82 individuals in 1975-85 and 59 in 1993-8 led to the establishment of a population of 42 territorial pairs in 2007, with the number of territorial adults increasing at 9.7%/year during 1997-2007. Survival rates of released birds were significantly lower than those of wild-bred birds, particularly during the first three years of life (74% survival for one year-old released birds vs. 82% for wild-bred; 94% survival for released birds aged four or more vs. 97% for wild-bred birds; overall probability of surviving until five years old of 37% for released birds vs. 53% for wild-bred). Breeding success of the established population is similar to that of the Norwegian population (in similar environmental conditions) but lower than populations elsewhere in Europe. Overall, breeding success and productivity have increased with time, as reintroduced birds get older (which significantly increases the probability of fledging young) and a higher proportion of the population consists of wild-bred birds (0.61 young fledged/territorial pair in 1993-2000 vs. 0.76 young fledged/territorial pair in 2003-7).