Open Access
How to translate text using browser tools
1 June 2016 Dispersal and Survival of Juvenile Golden Eagles (Aquila chrysaetos) from Finnmark, Northern Norway
Torgeir Nygård
Author Affiliations +
Abstract

The Golden Eagle (Aquila chrysaetos) in Fennoscandia has a widespread breeding range. In Norway, it spans from 58° in the south to 71° north in Finnmark County, making it likely the northernmost breeding population of this species in the world. To gain knowledge about their dispersal and movement behavior, we tagged 25 nestling Golden Eagles in Finnmark with satellite transmitters at the age of 7–11 wk during 2002–2011. About half of the birds made preliminary dispersals of more than 10 km from the nest, before dispersing permanently. The median date of permanent dispersal was 21 October. The main dispersal direction was southerly into the forested and agricultural areas in Sweden, but some birds also moved to Finland, Russia, and the Norwegian coast. The maximum dispersal distance from the natal area was ca. 1500 km. There was a return movement in the spring, with movement rates of about 20–30 km/day. The pattern of southerly migration in the autumn and northerly return in the spring was repeated over consecutive years. The overall survival rate was estimated at 58% during the first year of life, and 50% were alive after 2 yr. However, the birds that were hatched in the interior had higher survival rates than those hatched on the northernmost outer islands, and they also dispersed earlier than those from the coast. Illegal killing of Golden Eagles in northern Sweden was cause of mortality.

© 2016 The Raptor Research Foundation, Inc.
Torgeir Nygård "Dispersal and Survival of Juvenile Golden Eagles (Aquila chrysaetos) from Finnmark, Northern Norway," Journal of Raptor Research 50(2), 144-160, (1 June 2016). https://doi.org/10.3356/rapt-50-02-144-160.1
Received: 8 November 2013; Accepted: 1 December 2015; Published: 1 June 2016
KEYWORDS
Aquila chrysaetos
dispersal
golden eagle
migration
Norway
satellite tracking
Back to Top