Des Ursulines Building
300 Allée des Ursulines
418.723.1986 extension 1908
Arctic terrestrial ecosystems are often subject to temporal variations in biodiversity. For instance, lemming cycles are well known and studied throughout the Arctic. Fluctuations in the abundance of their main predators are also known, but information on variations in the abundance of other vertebrates and the mechanisms that drive them is limited. Spatial heterogeneity in the distribution of biodiversity is also observed in the Arctic tundra. Lakes and wetlands, for example, appear to be refuges for some species that are vulnerable to predation. Additionally, large colonies of migratory birds, such as the Greater Snow Geese, appear to have an aggregative effect on predators and a negative effect on other bird species. The information on these spatial variations is however sparse and the mechanisms that explain them are sometimes missing.
My project aims to describe the spatio-temporal variations of tundra-nesting bird communities to identify some of the underlying mechanisms. More specifically, we want to assess if the presence of prey refuges (wetlands or stony river banks, for example) shapes the spatio-temporal variations of some avian species. This project relies on data from Bylot island (73°N, 79°W; NU) long-term ecosystem monitoring (> 25 years). First, observational data of nesting birds species (nest monitoring and biodiversity transects) will be used to estimate the annual abundance and spatial distribution of each species in the study area. The second stage will consist of mapping and describing the prey refuges of the study area, using satellite imagery and field characterization. The final stage will be to test whether refuge usage by a species influences its spatial distribution and its annual abundance.
This project is part of a larger goal to understand the effects of biotic interactions on arctic biodiversity, especially in a context of global changes which tend to alter existing biotic interactions in ecosystems.