Evidence of Population Decline in Common Eiders Breeding in Western Greenland

Merkel, Flemming Ravn
Arctic Institute of North America
Greenland Institute of Natural Resources
Publication Date: 

ARCTIC Vol. 57, No. 1 (March 2004) P. 27–36
In the Arctic, there is great concern for several eider populations, including the northern common eider (Somateria mollissima borealis) breeding in Canada and Greenland. In 1998-2001, extensive ground surveys were conducted on 937 potential nesting islands in West Greenland, covering most of the districts of Ilulissat, Uummannaq, and Upernavik (69°15' N to 74°05' N). On 216 islands within 106 eider colonies, 4097 ±468 active nests were identified. In 15 colonies where comparable and well-documented surveys were conducted approximately 40 years ago, the study shows a population decline of 81% (from 3361 to 624 nests). A rough comparison shows that of 51 eider colonies surveyed in 1920, 1960, or 1965, 71% either were gone or had declined in breeding numbers when resurveyed in 1998-2001. At the colony level, the 1998-2001 surveys revealed large year-to-year variations in nesting numbers. The reason for the overall decline is not clear. However, there is circumstantial evidence that harvest of common eiders in West Greenland is a key factor. The results urgently call for more cautious management of the northern common eider population.
Key words: northern common eider, Somateria mollissima borealis, West Greenland, breeding population, population decline, harvest