Observations of moulting eider and breeding common eider Somateria mollissima at Nordaustlandet, Svalbard, in 1979

Abstract

A survey on the Common Eider Somateria mollissima in wing-feather moult and females with young was carried out in connection with Norsk Polarinstitutt's expedition to Svalbard in July and August 1979. A total of 3450 moulting eider were found on a water area of approximately 2500 km2; 18% of these were flightless. Females dominated in the population with about 82%. Of the breeding population, 109 females with 336 young were found. The average ratio of female to young has been calculated at 1 : 3.08. This ratio in relation to other studies of eider productivity is discussed briefly.