Evaluating the Sustainability of Harvest Among Northern Common Eiders Somateria Mollissima Borealis in Greenland and Canada

Abstract

Sustainable harvest, the extraction of game without affecting population viability, is a desirable approach to the use of wildlife. However, overharvest has been responsible for the decline of many wildlife populations globally, so there is an urgent need to balance human requirements while avoiding the severe depletion of wild populations. Northern common eiders Somateria mollissima borealis are heavily hunted in Canada and Greenland, but the effect of this intensive harvest has not been examined. We developed a population model to investigate the sustainability of the reported harvest, which consisted of two wintering areas in Greenland and Atlantic Canada and three breeding populations. The model indicated that harvest in Atlantic Canada was sustainable, but a number of conditions could lead to slow declines. In contrast, the annual winter harvest of 55,000–70,000 eiders reported during 1993–2000 in Greenland was not sustainable, and this conclusion held under a wide range of alternate conditions. The model indicated that harvest during late winter may have a greater effect on populations than harvest in early winter. We further refined the model to assume that at some low population level the success of hunters would decline and that harvest became a function of population size (a rate). This scenario had the expected and undesirable result of stabilizing populations at very low levels. Overall, our model suggests that the high harvest reported in Greenland during 1993–2000 endangers the sustainable use of the northern common eider population and that management actions are required. Common eider harvest levels in Greenland should be reduced by at least 40% of the 1993–2000 levels to stop projected declines, and allow for recovery of the decimated Greenland breeding population. Encouragingly, new hunting regulations were introduced in Greenland in 2002–2004, and harvest levels appear to be decreasing. If these harvest reductions continue, our population model could be used to re‐evaluate the status of populations in the two countries.

Composition of Eiders Harvested in Newfoundland

“…The size of the Common Eider population breeding in insular Newfoundland is small (7000 pairs of dresseri; S.G. Gilliland, unpubl. data); hence, most of the 100,000+ eiders that over-winter in Newfoundland waters (Gilliland et al 2009; Canadian Wildlife Service, St. John's, NL, Canada, unpubl. data) must originate from breeding areas along the coasts of Labrador, northern Québec, and the eastern Canadian Arctic.…”

Action plan for seabirds in Western-Nordic areas

“…Before the change in legislation in 2002, hunting pressure on common eiders was very high and probably unsustainable (Gilliland et al 2009). In the new regulations, the open season was shortened and the spring hunt was banned, leading to a ~ 70% decline in the hunting bag (F. Merkel pers.…”

Nesting Common Eider (<i>Somateria mollissima</i>) Population Quintuples in Northwest Greenland

“…The best-documented decline in Greenland is from the Ilulissat, Uummannaq, and Upernavik Districts in West Greenland (69˚15ʹ N to 74˚05ʹ N), where surveys from 1960 to 2000 showed an 81% reduction in the number of nests (Merkel, 2004a). Data suggest that the decline in this area was largely due to overharvesting pressure during the winter and early spring (Merkel, 2004b(Merkel, , 2010Gilliland et al, 2009); however, it is likely that other factors, such as bycatch from gill nets (Merkel, 2004b), egg collecting (Salomonsen, 1950;Merkel, 2004a), and nest predation by sled dogs, also contributed to this decline (Burnham et al, 2005).…”

“…From 2000 to 2007, the eider population of those districts increased by 212% (Merkel, 2010). Prior to this increase, the common eider population estimates for West Greenland had ranged from 12 000 to 15 000 breeding pairs (Merkel, 2002;Merkel et al, 2002;Gilliland et al, 2009).…”