Autumn use of Izembek Lagoon, Alaska, by brant from different breeding areas

Thirty-three adult brant (Branta bernicla) were radiomarked at 4 widely separated areas of the western Canadian arctic and 1 area in western Alaska during June-August 1987. Their use of the Izembek Lagoon on the Alaska Peninsula was monitored through the 1987 fall staging period (Sep-Dec). Eighty percent of the brant (n = 33), including ≥50% of individuals from each of the marking areas, were located at Izembek Lagoon. The mean arrival time for brant marked nearest to Izembek (the Yukon-Kuskokwim Delta [YK], Alas. [900 km away]) was 18 September, followed by those from the Mackenzie Delta, Northwest Territories, (3,500 km away) on 26 September, and brant from Victoria, Melville, and Prince Patrick islands, Northwest Territories [NT], (approx 4,500 km away) on 3 October. The mean duration of their stay at Izembek was 49 days. Within the 48-km-long lagoon there was considerable segregation between black brant (B. b. nigricans) and gray-bellied brant (intermediate between black brant and B. b. hrota).