Frédéric Dulude-de Broin

Université Laval
Ph.D. candidate

Supervisor: Pierre Legagneux
Audrey Durand, Université Laval
Start: 2020-09-01

Project

Influence of fox predation and the physical environment on prey distribution in an arctic terrestrial community.
The relative importance of biotic interactions as a drivers of species distribution is still controversial in ecology, despite strong evidence of their influence in some systems. Predation plays a central role in the structure and function of many arctic ecosystems. In heterogeneous landscapes, the movement of predators, shaped by physical constraints in the environment, the distribution of food resources, and social interactions, induces variation in the risk for prey. This heterogeneity in predation risk and how prey respond to it could be one of the key mechanisms driving species distribution in the Arctic tundra. The presence of refugia or environmental constraints that limit the availability of certain habitats could also influence species distribution by impacting both predator movements and prey habitat selection. Our main objective is to investigate the role of arctic fox predation and the physical environment in the distribution of prey in an Arctic terrestrial community. We will first assess how the abiotic environment (habitat, refugia and snowmelt pattern) influences prey (geese, shorebirds, passerines, etc.) nest site selection. Through a close collaboration between ecologists and computer scientists, we will then model arctic fox movements using step selection function fitted to fine scale GPS data. We will also explore the benefits of using new methods inspired by advances in reinforcement learning to model animal movement. The resulting movement model will provide the backbone for an individual based model of fox predation which will then be used to conduct large-scale simulations predicting predation risk throughout the study area of Bylot Island, and ultimately linking arctic fox predation to prey distribution. The project will contribute to our understanding of the relative role of biotic interactions in shaping species distribution and could highlight key drivers of biodiversity distribution in Arctic ecosystems.

Keywords

Écologie, Predator-prey dynamics, Mouvement ecology, Arctic fox, Arctic biodiversity