LAUSR

Arctic Russia is home to more than 90% of all Long-tailed Ducks in the Clangula hyemalis species from the Western Siberia/Northern Europe population. The breeding population in European Russia was estimated to be about 5 million birds in the 1960s, while today, estimates have declined to 1 million birds. Up until now, the main reasons for the overall population decline of the Long-tailed Duck were related to wintering conditions in the Baltic Sea. Our data indicate that the loss or deterioration of key breeding habitats in the Arctic regions of Russia is one important factor influencing the rapid population decline. Many key breeding habitats of the Long-tailed Duck were completely lost in the Bolshezemelskaya tundra, as this area was transformed into major oil and gas extraction sites. The transformation of these sites increased the disturbance and oil pollution of adjacent habitats, leading to the direct loss of certain key nesting sites and a marked and rapid decline of the breeding population of the Long-tailed Duck in the Bolshezemelskaya tundra. Oil-spills during transportation by sea may also be an important factor of decline in the Long-tailed Duck population. Meanwhile, in the Malozemelskaya tundra, which did not experience oil and gas development, the breeding population over the last decades remained stable. Urgent establishment of new protections in key breeding areas in Arctic Russia, sustainable population management, and new research programs are necessary for the conservation and enhancement of this globally threatened species.