Individual strategies, group dynamics and population regulation in singular cooperative breeders

对鸟类和哺乳动物种群密度调节的最详细研究集中在随着种群密度的增加，招募和存活率下降，最终限制种群规模的研究。然而，在一些物种中，随着密度的增加，招募和存活增加，从而产生被称为Allee效应的正相关关系。实证研究表明，这种影响比我们之前认为的更广泛，尽管我们对其原因和生态后果的了解仍然非常有限。这些影响似乎在合作繁殖者中特别明显，每组中有一只雌性垄断繁殖，非繁殖的成年雌性帮助她抚养后代，但是，尽管研究通常调查这些物种生殖策略的演变，但控制群体规模和种群密度的生态机制很少被探索。本研究将以野生短尾鼬(Suricata Suricatta)为模型，研究单一合作繁殖者的种群规模和种群密度的生态过程。它将检验群体规模与繁殖成功之间的正相关关系是群体成员发现捕食者能力增强的结果，并将确定群体规模是否受到从属雌性的扩散速度增加的限制，这是由于在大群体中生活的优势雌性越来越不容忍造成的。它将探讨群体一级的管理程序对人口一级的动态和人口统计的影响。最后，它将调查种群规模和种群动态如何受到降雨量、食物供应和疾病变化的影响。通过探索影响猫鼬种群动态的不寻常的生态机制，该项目将为其他受Allee效应影响的动物的管理和保护提供可靠的基础。

Most detailed studies of the regulation of population density in birds and mammals have focussed on studies where recruitment and survival decline as population density increases, eventually limiting population size. However, in some species, recruitment and survival increase with rising density, generating positive correlations known as Allee effects. Empirical studies show that effects of this kind are more widespread than was previously thought though our understanding of their causes and ecological consequences is still very limited. These effects appear to be particularly pronounced in cooperative breeders where one female in each group monopolises reproduction and non-breeding adults assist her to raise her offspring but, although studies have commonly investigated the evolution of reproductive strategies in these species, the ecological mechanisms controlling group size and population density have rarely been explored. This study will investigate the ecological processes limiting group size and population density in singular cooperative breeders using wild Kalahari meerkats (Suricata suricatta) as a model. It will test the prediction that positive correlations between group size and breeding success are a consequence of increases in the ability of group members to detect predators and will determine whether group size is limited by increasing rates of dispersal by subordinate females, caused by increasing intolerance by dominant females living in large groups. It will explore the effects of regulatory processes at the group level on dynamics and demography at the population level. Finally, it will investigate how group size and population dynamics are affected by variation in rainfall, food availability and disease. By exploring the unusual ecological mechanisms affecting population dynamics in meerkats, the project will provide an informed basis for the management and conservation of other animals subject to strong Allee effects.