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

从行为到人口统计学：陆地大型哺乳动物对北方环境全球变化反应的可塑性和相互依赖性

• 批准号: RGPIN-2016-05196
• 负责人: StLaurent, MartinHugues
• 金额: $ 2.04万
• 依托单位: Université du Québec à Rimouski
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2018
• 资助国家: 加拿大
• 起止时间: 2018-01-01 至 2019-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=665996
• 关键词: behaviour; demography; plasticity; interdependence; terrestrial

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.

北方森林传统上是由自然干扰(野火、风灾、虫害暴发)构成的，但在过去几十年里，人为足迹(栖息地丧失和碎片化)变得普遍，压倒了自然干扰，迫使野生动物适应快速变化的环境。了解这两类干扰对物种-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。我的研究计划旨在澄清我们对干扰影响动物生态的机制的理解，并描述观察到的反应的可塑性和相互依赖性。它得到了一个概念框架的支持，该框架综合了从行为和生理到生命率、人口和社区结构等一系列分级生物水平上不断增加的干扰严重程度的影响。基本假设表明，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统计结果，并部分解释了种群复原力的可变性。例如，动物可以根据不断增加的干扰水平调整其栖息地选择，最高可达一个阈值，超过这个阈值，行为调整是不可能的，生存受到影响，导致种群丰度和个体表现下降。我的工作重点是了解人类对人为干扰(如道路、伐木)的行为反应(空间使用、栖息地选择)。我最近开始在行为和生存之间建立联系，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GPS遥测来描述行为，并根据干扰强度的梯度监测个体的生存情况。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)行为与人口统计学(生存、生产力)的关系，方法是将运动和保真度与空间使用和栖息地选择联系起来；2)行为与生理的关系，使用皮质醇水平(代表慢性应激)，同时考虑行为的个体内和个体间差异。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的累积影响相结合。