Data from: Annual movement patterns of endangered ivory gulls: the importance of sea ice

The ivory gull (Pagophila eburnea) is an endangered seabird that spends its entire year in the Arctic environment. In the past three decades, threats from various sources have contributed to a >70% decline in Canada. To assess the annual habitat needs of this species, we attached satellite transmitters to 12 ivory gulls on Seymour Island, Nunavut in 2010, which provided up to four breeding seasons of tracking data. Analysis of migratory behaviour revealed considerable individual variation of post-breeding migratory route selection. Ivory gulls traveled a median of 74 days during post-breeding migration, but only 18 days during pre-breeding migration. In contrast to predictions, ivory gulls did not use the Greenland coast during migratory periods. Ivory gulls overwintered near the ice edge in Davis Strait, but also used the Labrador Sea in late February and March. We suggest that the timing of formation and recession and extent of sea ice plays a large role in ivory gull distribution and migratory timing.象牙鸥（ivory gull，学名Pagophila eburnea）是一种濒危海鸟，全年栖息于北极环境中。过去三十年间，各类来源的威胁导致加拿大境内的象牙鸥种群数量下降超70%。为评估该物种的年度栖息地需求，研究团队于2010年在努纳武特地区西摩岛为12只象牙鸥佩戴了卫星追踪器，由此获得了长达4个繁殖季的追踪数据。对迁徙行为的分析显示，繁殖后迁徙路线的选择存在显著的个体差异。象牙鸥的繁殖后迁徙时长中位数为74天，而繁殖前迁徙时长仅为18天。与此前预测相悖的是，象牙鸥在迁徙期间并未使用格陵兰岛沿岸区域。象牙鸥的越冬区域位于戴维斯海峡冰缘附近，同时也会在2月末至3月期间活动于拉布拉多海。本研究认为，海冰的形成、消退时机与覆盖范围，对象牙鸥的分布格局与迁徙时间具有显著影响。