PDF(Pubmed)
Abstract：
A significant body of evidence indicates that climate change is influencing many aspects of avian ecology. Yet, how climate change is affecting, and is expected to influence some aspects of the breeding ecology of cavity-nesting birds remains uncertain. To explore the potential linkage between timing of first clutch, and the influence of ambient temperature on hatching success, we used Eastern Bluebird (Sialia sialis) nest records over a nine-year period from Alabama, USA. We investigated changes to annual clutch initiation dates, as well as variability in hatching success associated with ambient air temperatures during the incubation period. Using a simple linear model, we observed earlier annual egg laying dates over the nine years of this study with a difference of 24 days between earliest egg-laying date of the season. Daily temperature minima increased 2 °C across the nine-year time frame of this study. These data also indicate that Eastern Bluebird hatching success was the highest when mean ambient air temperature during incubation was between 19 °C and 24 °C (78%, as opposed to 69% and 68% above and below this temperature range, respectively). Our findings of increasing maxima, earlier maxima each year, and the lower minima of temperatures within our study area could expand the breadth of temperatures experienced by nesting Eastern Bluebirds possibly exposing them to temperatures outside of what promotes nesting success. These findings with a cavity-nesting bird highlight an optimal range of ambient temperatures associated with highest hatching success, conditions likely to be affected by climate change.
摘要：
大量证据表明，气候变化正在影响鸟类生态的许多方面。然而，气候变化是如何影响的，并且预计会影响空腔筑巢鸟类繁殖生态的某些方面仍然不确定。为了探索第一离合器正时之间的潜在联系，以及环境温度对孵化成功的影响，我们使用了阿拉巴马州9年的东部蓝鸟（Sialiasialis）巢穴记录，美国。我们调查了年度离合器启动日期的变化，以及孵化期间与环境空气温度相关的孵化成功的可变性。使用简单的线性模型，在本研究的9年中，我们观察到了较早的年度产卵日期，与该季节最早的产卵日期相差24天。在这项研究的九年时间范围内，每日最低温度增加了2°C。这些数据还表明，当孵化期间的平均环境空气温度在19°C至24°C之间时，东方蓝鸟孵化成功率最高（78％，而高于和低于这个温度范围的69%和68%，分别)。我们增加最大值的发现，每年较早的最大值，我们研究区域内的最低温度可能会扩大筑巢东方蓝鸟所经历的温度范围，这可能会使它们暴露在促进筑巢成功的温度之外。这些发现对腔筑巢的鸟强调了与最高孵化成功率相关的最佳环境温度范围，可能受到气候变化影响的条件。
