From behaviour to demography: plasticity and interdependence of terrestrial large mammal responses to global changes in boreal environments

北方森林传统上是由自然干扰（野火、风吹、昆虫爆发）构成的，但在过去几十年中，人类足迹（栖息地丧失和破碎）变得普遍，压倒了自然干扰，迫使野生动物适应迅速变化的环境。了解这两种干扰对物种-栖息地关系、物种相互作用（捕食、竞争）以及最终种群波动（扩张、下降）的影响至关重要。我的研究计划旨在阐明我们对干扰影响动物生态学的机制的理解，并描述所观察到的反应的可塑性和相互依赖性。它是由一个概念框架集成的影响，越来越多的干扰严重性沿着一系列的层次生物水平，从行为和生理的生命率，人口和社区结构。基本的假设表明，生物水平是相互依赖的，个体之间的行为可塑性可能导致不同的人口结果，并部分解释了人口弹性的变异。例如，动物可以调整其栖息地选择，以增加干扰水平，达到一个阈值，超过这个阈值，行为调整是不可能的，生存受到损害，导致种群丰度和个体表现下降。我的工作一直专注于了解行为反应（空间使用，栖息地选择）人为干扰（如道路，伐木）。我最近开始建立行为与生存之间的联系，以说明行为决定对人口统计学的影响，并强调起作用的机制（例如非线性功能反应）。我正在使用林地驯鹿作为生物模型，它被认为是加拿大生物多样性不可替代的组成部分。我进一步考虑了它的主要捕食者（狼，黑熊，郊狼）和它的主要竞争对手（驼鹿）。我使用全球定位系统遥测来描述行为和监测生存的个人基础上沿着梯度的干扰强度。在接下来的5年里，我将继续对大型哺乳动物进行纵向遥测监测，以研究1）通过增加空间使用和栖息地选择的运动和保真度，将行为与人口统计学（生存，生产力）联系起来的关系，以及2）行为与生理学的关系，使用皮质醇水平（慢性压力的代理），同时考虑行为的个体内和个体间变化。我还将3）寻求应对干扰的生态阈值，并将4）将气候的协同影响与自然和人为干扰对行为和人口统计的累积影响结合起来。

Boreal forests were traditionally structured by natural disturbances (wildfires, windthrow, insect outbreaks), but anthropogenic footprint (habitat loss and fragmentation) became prevalent in the last decades, overriding natural disturbances and forcing wildlife to adapt to a rapidly changing environment. It is of prime importance to understand the impacts of both types of disturbances on species – habitat relationships, species interactions (predation, competition) and ultimately population fluctuations (expansion, decline). My research program aims at clarifying our understanding of the mechanisms by which disturbances influence animal ecology and at characterising the plasticity and interdependence of the responses observed. It is supported by a conceptual framework integrating the impacts of increasing disturbance severity along a succession of hierarchical biological levels ranging from behaviour and physiology to vital rates, population and community structure. The underlying hypotheses suggest that biological levels are interdependent and that behavioural plasticity among individuals could lead to different demographic outcomes and explain partially the variability in population resilience. For example, an animal could adjust its habitat selection to increasing levels of disturbances, up to a threshold above which behavioural adjustments are not possible and survival is compromised, resulting in a decrease in population abundance and individual performance. My work has been focused on understanding behavioural responses (space use, habitat selection) to human-induced disturbances (e.g. roads, logging). I recently began to establish links between behaviour and survival to illustrate the consequences of behavioural decisions on demography and to highlight the mechanisms at play (e.g. nonlinear functional responses). I am using woodland caribou, identified as an irreplaceable component of Canada's biodiversity, as a biological model. I further consider its major predators (wolf, black bear, coyote) and its main competitor (moose). I use GPS telemetry to describe behaviour and monitor survival on an individual basis along a gradient of disturbance intensity. Over the next 5-years phase, I will pursue my longitudinal telemetry monitoring of large mammals to study the relationships linking 1) behaviour to demography (survival, productivity) by adding movement and fidelity to space use and habitat selection, and 2) behaviour to physiology, using cortisol levels (proxy of chronic stress), while considering both intra- and interindividual variations in behaviour. I will also 3) seek ecological thresholds in response to disturbances and will 4) integrate the synergistic influence of climate to the cumulative impacts of natural and anthropogenic disturbances on behaviour and demography.