Whitenack Lauren E, Welklin Joseph F, Branch Carrie L, Sonnenberg Benjamin R, Pitera Angela M, Kozlovsky Dovid Y, Benedict Lauren M, Heinen Virginia K, Pravosudov Vladimir V
Department of Biology, Ecology, Evolution and Conservation Biology Graduate Program, University of Nevada, Reno, NV, USA.
Department of Psychology, University of Western Ontario, London, Canada.
R Soc Open Sci. 2023 Jun 21;10(6):230554. doi: 10.1098/rsos.230554. eCollection 2023 Jun.
Animals use climate-related environmental cues to fine-tune breeding timing and investment to match peak food availability. In birds, spring temperature is a commonly documented cue used to initiate breeding, but with global climate change, organisms are experiencing both directional changes in ambient temperatures and extreme year-to-year precipitation fluctuations. Montane environments exhibit complex climate patterns where temperatures and precipitation change along elevational gradients, and where exacerbated annual variation in precipitation has resulted in extreme swings between heavy snow and drought. We used 10 years of data to investigate how annual variation in climatic conditions is associated with differences in breeding phenology and reproductive performance in resident mountain chickadees () at two elevations in the northern Sierra Nevada mountains, USA. Variation in spring temperature was not associated with differences in breeding phenology across elevations in our system. Greater snow accumulation was associated with later breeding initiation at high, but not low, elevation. Brood size was reduced under drought, but only at low elevation. Our data suggest complex relationships between climate and avian reproduction and point to autumn climate as important for reproductive performance, likely via its effect on phenology and abundance of invertebrates.
动物利用与气候相关的环境线索来微调繁殖时间和投入，以匹配食物供应高峰。在鸟类中，春季温度是常用于启动繁殖的一个记录在案的线索，但随着全球气候变化，生物正经历环境温度的定向变化以及年际间极端的降水波动。山地环境呈现出复杂的气候模式，温度和降水沿海拔梯度变化，且降水年际变化加剧导致了大雪和干旱之间的极端波动。我们利用10年的数据，研究了美国内华达山脉北部两个海拔高度的留鸟山地山雀（）的气候条件年变化如何与繁殖物候和繁殖表现的差异相关联。在我们的系统中，春季温度变化与不同海拔间繁殖物候的差异无关。积雪增加与高海拔而非低海拔地区繁殖开始时间推迟有关。干旱条件下窝卵数减少，但仅在低海拔地区如此。我们的数据表明气候与鸟类繁殖之间存在复杂关系，并指出秋季气候对繁殖表现很重要，可能是通过其对物候和无脊椎动物数量的影响。
