Annual survival of Arctic terns in western Iceland
Annual survival of Arctic terns in western Iceland
复制标题
冰岛西部北极燕鸥的年存活率
作者：
A. Petersen;G. Robertson;Sverrir Thorstensen;M. Mallory
近几十年来，北大西洋地区的许多海鸟物种的数量出现了相当大的下降。其中一个物种是北极燕鸥(Sterna Paradisaea)，这是一种小型海鸟，每年迁徙的距离比任何其他海鸟都要远，其全球数量被认为正在下降。我们使用了冰岛西部弗拉蒂燕鸥栖息地50年(1974-2017)的雏鸟和成年燕鸥的条带数据，对冰岛这种物种的年度存活率进行了第一次评估。从刚孵化到第二年夏天的存活率估计为0.119 ± 0.024(SE)，而一岁以上的成鸟的年存活率高达0.952 ± 0.030。虽然我们的数据不足以评估成虫存活率的年度变化，但我们注意到近年来(自2000年以来)成虫存活率下降(0.851 ± 0.034)，这与当地沙枪种群的崩溃是一致的。成体存活率的下降，加上其他因素，可能是冰岛这种标志性物种数量下降的原因之一，冰岛是一个养育着世界20%-30%的繁殖人口的国家。
Many seabird species in the North Atlantic region have shown considerable declines in their populations during recent decades. One such species is the Arctic tern (Sterna paradisaea), a small seabird which migrates farther than any other seabird each year and whose global population is thought to be in decline. We used banding data of chicks and adults, spanning five decades (1974–2017) from a tern colony on Flatey, in western Iceland, to generate the first assessment of annual survival in this species in Iceland. Survival from just after hatching to the next summer was estimated to be 0.119 ± 0.024 (SE), while annual survival of adult birds (older than one year) was high at 0.952 ± 0.030. Although our data were insufficient to assess annual variation in adult survival, we noted a reduced survival (0.851 ± 0.034) in recent years (since 2000), coincident with a collapse in local sand lance populations. Reduced adult survival, along with other factors, is likely contributing to declining populations of this iconic species in Iceland, a country supporting 20–30% of the world’s breeding population.