Species ranges, diversity and life history of Neotropical montane birds

热带山区的鸟类比地球上任何其他地区都多。这种高度多样性的一个原因是，随着物种的退出和被其他物种取代，鸟类群落从低地到山顶发生了巨大的变化。我的研究旨在了解为什么许多物种仅限于热带山脉斜坡上的一部分海拔范围。换句话说，是什么阻止了低地的鸟类，它们可以飞很长的距离，而不是殖民栖息地只有500米上坡？此外，我的研究建立在长期监测数据库的基础上，以评估热带鸟类种群的稳定性，提供关键信息，以确定这些种群是在增长还是在下降。这项研究将在新热带地区的三个地点进行：秘鲁安第斯山脉的马努生物圈保护区、哥伦比亚中部的塔塔马国家公园和哥斯达黎加的蒙特韦尔德云雾森林。这些地区是主要的生物多样性“热点”。例如，在马努的一条沿着75公里的样带中，我们可以找到1100种鸟类，比整个北美都多。第一项倡议将测试关于鸟类如何与其他物种相互作用的替代假设（例如，竞争者、互利共生者、食物资源）或鸟类耐受极端环境条件的能力（例如，高海拔地区的寒冷温度）决定了物种在山腰上的生存位置。第二项举措将检查多年来重新捕获和监测的带状鸟类的数据，以估计热带物种的寿命以及种群数量的变化。它还将应用新技术来了解物种如何应对新环境。热带山区被视为气候变化将对动植物产生不成比例的巨大影响的地区。世界上超过四分之一的濒危鸟类栖息在这些地区。在下一个世纪，随着气温的升高，许多热带物种可能会被迫向上迁移。任何阻止它们殖民新环境的事情都会增加它们灭绝的风险。目前，我们对热带物种如何应对温度变化或物种间的相互作用是否会影响气候变暖时的上坡运动知之甚少。这项研究将提供这些数据，填补许多热带鸟类物种的重要知识空白，同时改善我们对这些生物多样性热点的保护策略。

Tropical mountains have more bird species than any other region on earth. One reason for this high diversity is that bird communities change dramatically from the lowlands to mountain tops as species drop out and are replaced by others. My research aims to understand why many species are restricted to just a portion of the elevation range available on the slopes of tropical mountains. In other words, what prevents lowland birds, which can fly long distances, from colonizing habitats only 500 meters upslope? Additionally, my research builds upon a long-term monitoring database to evaluate the stability of tropical bird populations, supplying crucial information to determine whether such populations are growing or in decline. This research will be carried out in three sites across the Neotropics: the Manu Biosphere Reserve in the Andes of Peru, Tatama National Park in central Colombia, and the Monteverde Cloud Forest of Costa Rica. These areas represent prime biodiversity "hotspots". For example, along a 75-km transect in Manu, we can find 1100 bird species, more than in all of North America. The first initiative will test alternative hypotheses regarding how the interactions of birds with other species (e.g., competitors, mutualists, food resources) or the ability of birds to tolerate extreme environmental conditions (e.g., cold temperatures at high altitudes) determine where species live on a mountainside. The second initiative will examine data from banded birds, which have been recaptured and monitored across years, to estimate how long tropical species live and how populations are changing. It will also apply new technologies to understand how species will respond to novel environments. Tropical mountains have been targeted as regions where climate change will have disproportionately large impacts on plants and animals. More than a quarter of the world's endangered bird species inhabit these regions. Over the next century, many tropical species could be forced to move upslope as temperatures increase. Anything that prevents them from colonizing new environments will increase their risk of extinction. Currently, we know very little about how tropical species will respond to changing temperatures or whether species interactions could affect upslope movements in response to warming. This research will provide these data and fill important knowledge gaps for many tropical bird species while improving our conservation strategies for these biodiversity hotspots.