Breeding density and population of little auks (Alle alle) in a Northwest Greenland colony

The little auk population of the Thule district in Greenland is generally believed to be the largest anywhere and to comprise more than half of the world population, although published numbers have largely been conjectural. In 1996/1997 we estimated breeding density of little auks at Hakluyt Island in this district by colour-marking a number of birds in three study plots and subsequently counting marked and unmarked birds present in the plots. The density estimate considered most representative of the colony was 1.8 birds/m2 or 0.73 pairs/m2 (±7%). From surveys of the inhabitated area of the scree slopes, this density implies a total little auk population for the island of 130,000 pairs. An extrapolation to the entire Thule district suggests a population in the area of at least 15 million pairs, which is in general agreement with previously published assumptions.