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Article
Bjorn Helander, Auteur ; Frank Hailer, Auteur ; Carles Vilà, AuteurIdentifying the sex of bird nestlings is relevant to studies of behaviour and ecology and is often a central issue in the management of endangered or captive populations. The white-tailed eagle Haliaeetus albicilla is a formerly threatened Euras[...]
Article
Peter Hellstrom, Auteur ; Bjorn Helander, AuteurSwedish diurnal raptor and owl monitoring is to a large extent based on species specific projects with long-standing traditions, migration counts at specific migration hot-spots, and a nation-wide bird survey. The best-known and long-lived proje[...]
Article
The White-tailed Eagle Haliaeetus albicilla was fairly common in Sweden until the early or mid 19th century. but was subsequently brought close to extinction by persecution. When legal protection was enforced in 1924, a few tens of breeding pair[...]
