Low abundance of king elder nests during low lemming years in northeast Greenland

Long-term surveys on Traill Island (Northeast Greenland) show that numbers of king elder (Somateria spectabilis) nests are correlated with high densit ies of collared lemming (Dicrostonyx groenlandicus). These observations mat ch other zoological records from this region and agree with similar observa tions recorded elsewhere for arctic geese. Processes at work may be related to the fact that mammalian predators focus on lemmings when lemming number s are high, but exert higher predation pressure on other prey at low lemmin g densities. Predators seem to increase their search effort during such low lemming years, thus increasing the likelihood that they will discover elde r nests. This study highlights the importance of studying patterns at the c ommunity level in any attempt to interpret cyclic fluctuations in northern ecosystems.