Post-moult distribution and abundance of white-fronted geese and Canada geese in West Greenland in 2007

Abstract

Rapid increases in North American Canada geese (Branta canadensis) summering in West Greenland since the mid-1980s compare with declines in the endemic population of white-fronted geese (Anser albifrons flavirostris) nesting in the same region since 1999 (wintering in Europe). To provide information on the distribution and abundance of the two species in Greenland during the prelude to the autumn migration back to winter quarters, we here report on the first ever post-moult aerial surveys of West Greenland between 64° and 73°N (from regular transects and transit reconnaissance flights in August 2007), which located 1888 Greenland white-fronted geese and 6071 Canada geese. Strip transect surveys found 733 Greenland white-fronted geese and 1318 Canada geese in the 993 km2 surveyed, which, given a white-fronted goose global population of 23 200 in winter 2007/08, suggests more than 41 500 Canada geese inWest Greenland post-moult in 2007. Virtually no geese were found south of 66°N. The Eqalummiut nunaat–Nassuttuup nunaa and Naternaq Ramsar wetlands of international importance, and lowland Disko Island, Saqqaqdalen and Svartenhuk supported the highest densities of both species. Results confirmed that areas important for both species during spring, nesting and moulting periods retain high densities of post-moulting geese. Canada and white-fronted geese rarely occurred together within 2.5 km ¥ 400 m transect sectors, as found during breeding surveys. Only in western Svartenhuk and western Disko were there Canada goose concentrations that could potentially support an intensive autumn hunt, whilst avoiding disturbance to white-fronted geese.