Department of Natural Resource Ecology and Management, Oklahoma State University, Stillwater, OK 74078.
South Central Climate Adaptation Science Center, Norman, OK 73019.
Proc Natl Acad Sci U S A. 2024 Mar 19;121(12):e2308433121. doi: 10.1073/pnas.2308433121. Epub 2024 Mar 4.
The green-up of vegetation in spring brings a pulse of food resources that many animals track during migration. However, green-up phenology is changing with climate change, posing an immense challenge for species that time their migrations to coincide with these resource pulses. We evaluated changes in green-up phenology from 2002 to 2021 in relation to the migrations of 150 Western-Hemisphere bird species using eBird citizen science data. We found that green-up phenology has changed within bird migration routes, and yet the migrations of most species align more closely with long-term averages of green-up than with current conditions. Changing green-up strongly influenced phenological mismatches, especially for longer-distance migrants. These results reveal that bird migration may have limited flexibility to adjust to changing vegetation phenology and emphasize the mounting challenge migratory animals face in following en route resources in a changing climate.
春季植被变绿带来了许多动物在迁徙过程中追踪的食物资源脉冲。然而，随着气候变化，植被变绿的物候期正在发生变化，这给那些将迁徙时间与这些资源脉冲相吻合的物种带来了巨大的挑战。我们使用 eBird 公民科学数据，评估了 2002 年至 2021 年与 150 种西半球鸟类迁徙相关的变绿期物候变化。我们发现，在鸟类迁徙路线内，变绿期物候已经发生了变化，但大多数物种的迁徙与变绿期的长期平均值更为吻合，而不是与当前的条件相吻合。变绿期的变化强烈影响了物候期的不匹配，特别是对长距离迁徙的物种影响更大。这些结果表明，鸟类迁徙可能对调整植被变绿期的变化的灵活性有限，并且强调了在不断变化的气候中，迁徙动物在沿途资源的跟踪方面面临的挑战越来越大。
