Natural History of the Gyrfalcon in the Central Canadian Arctic

• Published in: ARCTIC
• Main Authors: Poole, K.G., Bromley, R.G.
• Format: Article in Journal/Newspaper
• Language: English
• Published: The Arctic Institute of North America 1988
• Subjects: Animal mortality; Animal population; Animal reproduction; Bird nesting; Gyrfalcons; Elu Inlet region; Nunavut; Melville Sound region; Victoria Island; N.W.T./Nunavut; Arctic; Elu Inlet; Melville Sound; Northwest Territories; Arctique*; Falco rusticolus; gyrfalcon
• Online Access: https://journalhosting.ucalgary.ca/index.php/arctic/article/view/64743

A population of breeding gyrfalcons was studied from 1982 to 1986 on a 2000 sq km area in the central Arctic of the Northwest Territories. Each year 14-18 territories were occupied. The mean internest distance was 10.6 km, giving one of the highest recorded densities for the species. There was a tendency for regularity in spacing of territories. Most (85%) nests were in abandoned stick nests of common ravens or golden eagles. Rough-legged hawk nests were not used by gyrfalcons, despite numerous available. Mean date of initiation of laying was 8 May. Mean size of clutch was 3.80 and of brood was 2.53, and mean productivity was 1.50 fledged young. A reduction of 48% from estimated number of eggs laid to number of fledglings was determined. Reproductive success declined with increased severity of spring weather, notably increased days and amount of precipitation.Key words: gyrfalcon (Falco rusticolus), natural history, reproductive ecology, central Arctic Mots clés: gerfaut (Falco rusticolus), histoire naturelle, écologie de la reproduction, région centrale arctique