Perturbation, Social Rewiring, and Population Dynamics in Animal Societies

许多动物物种在野外面临灭绝的危险，了解这些种群面临的威胁对于确保它们的保护至关重要。在许多物种中，社会关系对个体生存至关重要，个体社会关系的强度和质量可以预测其繁殖成功。对于长寿的动物来说，社会伙伴的死亡（扰动）代表着一种重大的动荡，可能对生存产生长期的负面影响。因此，我们期望个体在失去社会伙伴后重新连接和调整他们的社会关系，以减轻失去伙伴的负面影响。社会重组策略可能是决定长寿动物种群对环境变化的适应力的关键。具有个体适应性的社会重组战略（例如，提高个体生存率）将改变全球社会网络结构，这可能对人口的复原力产生积极或消极的影响。例如，一个群体内的社会联系程度可以决定该群体对衰退甚至灭绝的脆弱性，例如，因为它对疾病爆发的敏感性。我们预测，这种反馈系统（社会网络结构影响生存/繁殖，反之亦然）将推动人口动态，在人口减少的情况下，可能会加速或延迟人口下降。然而，目前我们对动物在野生种群中使用的重新布线策略及其对种群弹性的影响知之甚少。本项目将利用长期监测美国华盛顿州和加拿大不列颠哥伦比亚省沿海沃茨高度社会化的虎鲸种群所提供的独特机会，我们可以获得超过45年的所有个体的详细人口统计和社会数据。该项目将量化个人在社会伴侣死亡后使用的重新布线策略，并确定个人如何调节现有关系并形成新的关系。此外，利用长期数据，该项目将确定个人重新布线战略对人口轨迹的影响以及社会结构和人口统计之间的反馈。这项工作的成果将提供一个新的基本了解人口动态和社会行为之间的联系，并将提高我们的能力，预测人口轨迹和设计保护干预措施的社会物种。

Many animal species are at risk of extinction in the wild and understanding the threats to these populations is essential to ensure their conservation. In many species, social relationships are essential for individual survival and the strength and quality of an individuals' social relationships can predict their reproductive success. For long-lived animals, the death of social partners (perturbation) represents a major upheaval that can have long-lasting negative effects on survival. We thus expect individuals to rewire and adjust their social relationships after the loss of a social partner to mitigate the negative effects of partner loss. Social rewiring strategies are likely to be crucial in determining the resilience of long-lived animal populations to environmental change. Social rewiring strategies that are individually adaptive (e.g. that improve individual survival) will alter the global social network structure, which may have positive or negative consequences for population resilience. For example, the degree of social connectivity within a population can determine the population's vulnerability to decline or even extinction, for example, because of its susceptibility to a disease outbreak. We predict that this system of feedbacks (social network structure affects survival/reproduction and vice versa) will drive population dynamics, which in shrinking populations may hasten or delay population decline. Currently however, we have little understanding of the rewiring strategies that animals use in wild populations or their implications for population resilience. This project will capitalize on the unique opportunity provided by the long-term monitoring of a population of highly social resident killer whales in the coastal waters off Washington State, USA, and British Columbia, Canada, for which we have access to over 45 years of detailed demographic and social data on all individuals. The project will quantify the rewiring strategies that individuals use following the death of a social partner and determine how individuals regulate their existing relationships and form new ones. Moreover, using the long-term data the project will determine the consequences of individual rewiring strategies for population trajectories and feedbacks between social structure and demography. Outputs of this work will provide a new fundamental understanding of the link between population dynamics and social behaviour and will improve our ability to forecast population trajectories and design conservation interventions in social species.