Gillies Natasha, Thorley Jack, Weimerskirch Henri, Jenouvrier Stéphanie, Barbraud Christophe, Delord Karine, Patrick Samantha C
School of Environmental Sciences University of Liverpool Liverpool UK.
Department of Zoology University of Cambridge Cambridge UK.
Ecol Evol. 2024 Nov 28;14(12):e70631. doi: 10.1002/ece3.70631. eCollection 2024 Dec.
Climate change has marked effects on global weather patterns and oceanic systems, impacting animal behaviour and fitness in potentially profound ways. Despite this, we lack detailed information about species' responses to climatic variation. Using an 11-year tracking dataset of over 300 individual birds, we explore the consequences of variation in the southern annular mode (SAM) and southern oscillation index (SOI) for individual behaviour and fitness in wandering albatrosses breeding in the Southern Indian Ocean. Our results reveal distinct responses between males and females to climatic variation that align with the impacts of each climatic index on the distinct foraging ranges of each sex. In positive SAM phases, linked to poorer foraging conditions in female ranges and better conditions in male ranges, females exhibited behaviour consistent with reduced foraging success: that is, fewer prey capture attempts and more movement between feeding patches. Males, on the other hand, showed no behavioural change. During positive SOI phases, associated with good foraging conditions in both male and female foraging ranges, both sexes showed evidence of more successful foraging, with birds engaging in more search behaviour, and taking shorter trips with fewer prey capture attempts, together indicating increased food intake per unit time. We found limited evidence for a role of individual variation, as measured through differences in personality, suggesting that plastic responses to climate are sufficiently important so as to obscure inter-individual variation. Supporting this was the finding that individual breeding success was unaffected by climatic variation, suggesting that plastic foraging behaviour allows albatrosses to mitigate climate impacts and maintain reproductive output.
气候变化对全球气候模式和海洋系统产生了显著影响，可能以深远的方式影响动物的行为和健康状况。尽管如此，我们仍缺乏关于物种对气候变化反应的详细信息。利用一个包含300多只个体鸟类的11年跟踪数据集，我们探讨了南环形模态（SAM）和南方涛动指数（SOI）的变化对在印度洋南部繁殖的漂泊信天翁个体行为和健康状况的影响。我们的结果揭示了雄性和雌性对气候变化的不同反应，这与每个气候指数对不同性别独特觅食范围的影响相一致。在正的SAM阶段，与雌性觅食范围内较差的觅食条件和雄性觅食范围内较好的条件相关，雌性表现出与觅食成功率降低相一致的行为：即更少的猎物捕获尝试和在觅食斑块之间更多的移动。另一方面，雄性没有表现出行为变化。在正的SOI阶段，与雄性和雌性觅食范围内良好的觅食条件相关，两性都表现出觅食更成功的迹象，鸟类进行更多的搜索行为，出行距离更短，猎物捕获尝试更少，这共同表明单位时间内食物摄入量增加。我们发现通过个性差异衡量的个体差异所起的作用证据有限，这表明对气候的可塑性反应非常重要，以至于掩盖了个体间的差异。支持这一点的是个体繁殖成功率不受气候变化影响这一发现，这表明可塑性觅食行为使信天翁能够减轻气候影响并维持繁殖产出。
