Seasonal Movements of Gyrfalcons (Falco rusticolus) Include Extensive Periods at Sea.

• DOI: 10.4080/gpcw.2011.0211
• Publication Date: 2012-01-03T20:57:01Z
• Authors: Kurt Burnham
• Keywords: 0106 biological sciences; 01 natural sciences

Little information exists on the movements of Gyrfalcons (Falco rusticolus) outside breeding season, particularly amongst High Arctic populations, with almost all current knowledge based Low populations.This study is first to provide data summer and winter ranges migration distances.We highlight a behavior previously unknown in Gyrfalcons, which birds sea ice far from land.During 2000-2004, were collected 48 tagged satellite transmitters three parts Greenland: Thule (northwest), Kangerlussuaq (central-west), Scoresbysund (central-east).Breeding home-range size for seven adult females varied 140 1,197 km 2 was 489 503 two males.Complete outward migrations wintering areas recorded individuals: an male travelled 3,137 over 38-day period (83 km/day) northern Ellesmere Island southern Greenland, female 4,234 Greenland (via eastern Canada) 83-day (51 km/day), 391 13-day (30 km/day).Significant differences found between west coast (383-6,657 ) east (26,810 -63,647 ).Several falcons had no obvious home-ranges continually during non-breeding period, at times spending up 40 consecutive days sea, presumably resting icebergs feeding seabirds.During winter, one juvenile 4,548 approximately 200-day more than half that time ocean Iceland.These are some largest ever documented raptors documentation long-term use pelagic habitats by any falcon.In general, return faster ones.This highlights importance fjord regions southwest as habitat provides detailed insights into complex highly variable movement patterns species.