Current status and recent dynamics of the Black Brant Branta bernicla breeding population

摘要: We summarize current knowledge about the distribution of Pacific Black Brant and recent dynamics colonies, particularly on Yukon-Kuskokwim (Y-K) Delta, Alaska. About 20,000 nests are required to produce number young in autumn flight using estimates clutch size, hatching success gosling survival based colonies Y-K Delta. More than 80% population can be accounted for currently Most moulting individuals that did not breed, or were unsuccessful, unaccounted late summer. Numbers nesting major Delta declined >60% early 1980s, most likely as a result local subsistence harvest combined with predation by arctic foxes. Effective management this requires better understanding breeding birds, importance habitat colony role both sport dynamics.