Doctoral Dissertation Improvement: Behavioral and Ecological Interactions of Lemurs and Raptors in Ranomafana National Park, Madagascar

狐猴给试图理解它们的社会行为的科学家们带来了一个难题，因为它们不符合大多数猴子和类人猿的一般社会模式。对这种差异的一种可能的解释是，马达加斯加(现代狐猴物种的家园)的捕食者比其他灵长类动物生活的地区更少、更不危险。坊间研究对这一假设提出了质疑，但关于狐猴捕食的系统数据很少。这项关于马达加斯加拉诺马法纳国家公园狐猴和猛禽的行为和生态相互作用的研究旨在提供以下信息：1)狐猴和昼夜猛禽之间的特定生态相互作用；2)狐猴对不同捕食者物种的反捕食者行为。第一个问题将通过测量马达加斯加四种最大的昼夜猛禽(短角叉尾鹦鹉、大头叉尾猛禽、放射状多尾狐猴、真狐猴)对狐猴造成的实际死亡率来解决。这些猛禽中的每一种都将成为巢穴观察、猎物残留收集和无线电跟踪研究的重点，这些研究旨在测量每个猛禽物种杀死的狐猴数量、发生死亡的区域以及猎物的数量。此外，两个实验将解决狐猴对现有捕食者协会的行为反应。第一项实验涉及捕食者发声回放三种不同体型的狐猴：斑狐猴(Propithecus Diadema Edwardsi)、红宝石狐猴(Eulemur Fulvus Rufus)和温和的狐猴(Hapalemur Griseus)。第二个实验包括暴露三组独立的食肉动物，以模拟鸟类和陆地捕食者。对猛禽和狐猴数据的分析将有助于清楚地了解猛禽捕食对狐猴的生态影响以及狐猴对捕食风险的行为反应。

Lemurs have presented a puzzle to scientists trying to understand their social behavior, because they do not conform to the general social patterns found in most monkeys and apes. One of the possible explanations for this difference assumes that Madagascar (the home of modern lemur species) has fewer and less dangerous predators than other areas where primates live. Anecdotal studies have questioned this assumption, but there are few systematic data concerning predation on lemurs. This study of the behavioral and ecological interactions of lemurs and raptors in Ranomafana National Park, Madagascar is designed to provide information on 1) the specific ecological interactions between lemurs and diurnal birds of prey, and 2) anti-predator behaviors of lemurs in response to distinct predator species. The first question will be addressed by measuring the actual rate of mortality on lemurs imposed by the four largest diurnal birds of prey in Madagascar (Buteo brachypterus, Accipiter henstii, Polyboroides radiatus, Eutriorchis astur). Each of these raptors will be the focus of nest observations, prey remain collections, and radio-tracking studies designed to measure the number of lemurs killed by each raptor species, the area over which this mortality occurs, and the prey population size. In addition, two experiments will address the behavioral responses of lemurs to the existing predator guild. The first experiment involves predator vocalization play backs to three species of lemurs with varying body sizes: the diademed sifaka (Propithecus diadema edwardsi), the rufous lemur (Eulemur fulvus rufus), and the gentle lemur (Hapalemur griseus). The second experiment consists of exposing three independent groups of diademed sifakas to model avian and terrestrial predators. The analysis of both raptor and lemur data will provide a clear understanding of the ecological influence of raptor predation on lemurs as well as the behavioral responses of lemurs to predation risk.