Nutritional ecology and predator sensitive foraging in sympatric Lemur catta and propithecus verreauxi verreauxi in spiny and scrub forest habitats in southern Madagascar

这个拟议的项目扩展了我之前关于群居灵长类动物的成本和收益的工作，这一次研究了在马达加斯加南部灌木丛和多刺森林栖息地共存的环尾狐猴和Verreaux‘s sifaka在饮食方面的性别和生殖状态差异，并调查了这些物种对捕食者敏感的觅食策略。马达加斯加南部极端的资源季节性导致了明显的生殖同步性的演变，在食物稀缺的时候，对生殖雌性动物的能量需求很高。为了确定这些雌性如何应对这些需求，我将调查在物种内和物种之间，生殖雌性和非生殖群体成员之间的营养摄入量、摄食时间和摄食量是否存在差异。每个物种的饮食中都含有大量的单宁，由于其抗流产、抗寄生虫和促进哺乳的特性，可能会使生殖雌性受益，因此，我还将测试单宁的消费是否存在性别和生殖状态的差异。由于这两个物种在开阔的灌木丛和多刺的森林生境中都很容易被捕食，我将研究群体规模和繁殖状态对捕食者敏感觅食策略的影响(例如，在不同规模的群体和栖息地的不同区域觅食时的警觉性和群体凝聚力模式)。该项目的结果可以与在差异很大的走廊森林栖息地对同一物种的类似研究进行比较，并可以阐明栖息地变化是否以及如何影响种群内和种群之间生殖和非生殖动物之间的营养和觅食差异。这项研究的信息还有助于解释共域哺乳动物物种的觅食和觅食模式的演变，特别是在马达加斯加的灌木丛和多刺森林等恶劣的季节性环境中，以及这种模式最终可能如何影响繁殖成功。

The proposed project expands upon my previous work related to costs and benefits of group living in primates, this time examining sex and reproductive state differences in diet in co-existing ring-tailed lemurs and Verreaux's sifaka in a scrub and spiny forest habitats in southern Madagascar, and investigating predator-sensitive foraging strategies in these species. Extreme resource seasonality in southern Madagascar has led to the evolution of marked reproductive synchrony, with high energetic demands placed upon reproductive females at a time when food is scarce. To determine how such females cope with these demands, I will investigate whether nutrient intake, time spent feeding, and amount of food ingested differs between reproductive females and non-reproductive group members both within and between species. The diet of each species contains high amounts of tannins, which can potentially benefit reproductive females because of its anti-abortive, anti-parasitic, and lactation promoting properties, thus, I will also test whether sex and reproductive state differences exist in tannin consumption. Because both species are vulnerable to predation in open scrub and spiny forest habitats, I will examine effects of group size and reproductive state on predator sensitive foraging strategies (e.g. vigilance and group cohesion patterns while foraging in different sized groups and in different areas of the habitat). Results from this project can be compared with similar studies of the same species in vastly different gallery forest habitat, and can elucidate if and how habitat variation influences nutritional and foraging differences between reproductive and non-reproductive animals both within and between populations. Information from the study can also help explain the evolution of feeding and foraging patterns in sympatric mammalian species, particularly in harsh seasonal environments such as Madagascar's scrub and spiny forests, and how such patterns may ultimately affect reproductive success.