School of Environmental and Forest Sciences, University of Washington, Seattle, WA, USA.
Civil and Environmental Engineering, University of Washington, Seattle, WA, USA.
Commun Biol. 2024 Nov 15;7(1):1515. doi: 10.1038/s42003-024-07195-1.
Extreme weather events are becoming more frequent, with poorly known consequences for wildlife. In December 2021, an atmospheric river brought record-shattering amounts of rain and snow to interior Alaska, creating conditions expected to cause mass mortality in grazing ungulate populations that need to access ground forage. We characterized snowpack conditions following the storm and used a 36-year monitoring dataset to quantify impacts on caribou (Rangifer tarandus) and their primary predator, wolves (Canis lupus). December precipitation was 7.3 SD above the 99-year mean and 2.5-fold higher than the prior record, with a return period of 333 years. However, ice thickness within the snowpack was highly variable across vegetation types, and caribou shifted to use higher elevations that can blow free of snow. Caribou and wolf mortality rates were 1.3-1.8 SD above normal and caribou population growth rates were low but similar to recent years, indicating a surprisingly weak demographic response. These findings indicate that landscape diversity may bolster resistance of wildlife populations to short-term, potentially devastating effects of extreme weather.
极端天气事件变得更加频繁，对野生动物的未知影响。2021 年 12 月，一场大气河流给阿拉斯加内陆带来了创纪录的暴雨和降雪，这种情况预计会导致需要接触地面草料的食草有蹄类动物大量死亡。我们描述了风暴后的积雪情况，并使用 36 年的监测数据集来量化对驯鹿（Rangifer tarandus）及其主要捕食者狼（Canis lupus）的影响。12 月的降水量比 99 年平均值高出 7.3 个标准差，是此前记录的 2.5 倍，重现期为 333 年。然而，积雪内的冰厚在不同植被类型之间差异很大，驯鹿转移到了可以吹走积雪的高海拔地区。驯鹿和狼的死亡率比正常值高出 1.3-1.8 个标准差，而驯鹿的种群增长率较低，但与近年来相似，这表明人口的反应出人意料地微弱。这些发现表明，景观多样性可能增强了野生动物种群对短期、潜在破坏性极端天气影响的抵抗力。
