Collaborative Research: Forest fragmentation and climate change result in understory warming that adversely affects tropical avian biodiversity at the BDFFP.

热带鸟类有麻烦了，尤其是那些主要吃昆虫的鸟类。森林的大小面积都在减少，但小森林或“片断”的速度更快。暴露在阳光下沿着边缘的碎片导致他们的内部变得更热，更干燥，这降低了许多鸟类的栖息地质量。科学家们并不确切地知道温暖和干燥的环境是如何给鸟类带来麻烦的，但他们认为这是由于食物减少和压力增加。在这项研究中，研究人员将研究更长和更热的旱季是否是连续森林中鸟类数量下降的原因，以及哪些物种最容易受到气候变化的影响。为此，他们将收集生理数据，并将其与过去四十年的气候数据结合联合收割机，以了解气候和森林条件对鸟类饮食，健康和生存的相对作用。研究结果将提高我们对森林损失和气候变化如何影响鸟类的理解，以及我们可能减轻生物多样性损失的方法。研究表明，片断化森林中残存的鸟类群落是未来连续森林中鸟类群落的前兆。增加的生理压力和/或饮食专业化可能是全球变化下鸟类生存和繁殖成功的决定因素。该项目有三个目标：（1）通过在一系列生存模型中纳入40年的气候和鸟类环志数据，评估气候变化作为森林破碎化项目（BDFFP）连续森林中长期鸟类减少的主要驱动力的影响。(2)通过人口统计学建模，确定气候变化和碎片化对BDFFP鸟类种群生存能力的相互影响。(3)测量模型鸟类（两个经历下降：Turdus albicollis和Willisornis poecilinotus，两个经历人口增长：Calyptorhynchus spirurus和Pithys albifrons）的饮食和行为专业化如何与林下小气候的变化相互作用，以影响健身。研究人员将使用eDNA和同位素生态位分析（来自粪便样本，羽毛和脚趾甲）的组合来测量饮食，并使用B-OH丁酸酯，甘油三酯和皮质酮的组合来测量压力，跨季节以及连续和破碎的森林之间。结果将产生的作用，生态位专业化和林下干燥驱动热带鸟类对森林破碎化和气候变化的人口反应发挥机械的见解。这个奖项反映了NSF的法定使命，并已被认为是值得通过使用基金会的智力价值和更广泛的影响审查标准进行评估的支持。

Tropical birds are in trouble, especially those that eat mostly insects. Population declines are taking place in both large and small areas of forest, although at a faster rate in small forests or “fragments”. Exposure to sun along the edges of fragments causes their interior to become hotter and drier, which reduces habitat quality for many birds. Scientists do not know exactly how warmer and drier conditions cause trouble for birds, but they think it is due to less food and more stress. In this study, researchers will study whether longer and hotter dry seasons are responsible for the decline of birds in continuous forests and which species are most susceptible to changes in climate. To do this, they will collect physiological data and combine it with climate data from the past forty years to understand the relative role of climate and forest condition on birds’ diet, health and survival. Results will improve our understanding of how forest loss and climate change affect birds, and ways in which we might mitigate the loss of biodiversity. The PIs posit that remnant bird communities in forest fragments are a precursor of future bird assemblages in continuous forest. Increased physiological stress and/or dietary specialization are likely determinants of avian survival and reproductive success under global change. This project has three objectives: (1) Assess the impact of climate change as the primary driver of long-term bird declines in continuous forest at the Biological Dynamics of Forest Fragmentation Project (BDFFP) through the inclusion of 40 years of climate and bird banding data in a series of survival models. (2) Determine the interactive effects of climate change and fragmentation on the viability of bird populations at BDFFP through demographic modeling. (3) Measure how dietary and behavioral specialization of model bird species (two experiencing declines: Turdus albicollis and Willisornis poecilinotus, and two experiencing population growth: Calyptorhynchus spirurus and Pithys albifrons) interact with variation in understory microclimates to affect fitness. Researchers will measure diet using a combination of eDNA and isotopic niche analysis (from fecal samples, feathers, and toe nails) and stress using a combination of B-OH butyrate, triglyceride, and corticosterone, across seasons and between continuous and fragmented forests. Results will yield mechanistic insights into the role that niche specialization and understory drying play in driving demographic responses of tropical birds to forest fragmentation and climate change.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.