Supervised by:

Joël Bêty (Regular member)

Co-supervised by:

Dominique Gravel (Regular member)

Research project description

Characterizing the connectivity of an Arctic food web with the rest of the world through animal migration: the case of Bylot Island.

IntroductionFood webs rarely take into account the consequences of animal migration movements that generate intermittent trophic interactions and exchanges of energy, nutrients and contaminants between far ecosystems. The anthropogenic and environmental pressures acting on migratory species are multiple and can act during several periods of their life cycle and in far environments. Considering the increasing proportion of migratory species with latitude, polar environments are likely subject to a greater influence of migratory species on the dynamic of local networks. It is well recognized that Arctic-nesting birds frequently travel significant distances, however, the connectivity between Arctic ecosystems, wintering grounds and migratory stopover sites to which they are connected remains very poorly detailed. ObjectivesThe main objective of this study will be to develop a detailed methodology to define the connectivity of the Arctic tundra of Bylot Island with the rest of the world through an animal migration network. This objective will be achieved in three steps: Step 1. Delimiting and characterizing at the biome scale: the wintering grounds, migratory stopover sites and partial migration areas of migratory and partially migratory species of the Arctic tundra of Bylot Island. Step 2. Representing through a tripartite network (three layers with different node types) the connectivity through animal migration of the Arctic tundra of Bylot Island (first layer) with the wintering grounds (second layer) and the migratory stopover sites or partial migration areas (third layer) of migratory and partially migratory species. Step 3. Describing the tripartite network of Bylot Island connectivity according to basic proprieties derived from the network theory. Study sitesThe study aims to highlight the connectivity of the Arctic tundra of Bylot Island, an 11 000 km2 island located in the Canadian High-Arctic at the northern tip of Baffin Island, Nunavut, Canada. The island is mostly covered by mountains and glaciers, however 1 600 km2 of low altitude tundra and wetlands are found in the southern part of the island. This fairly productive area is generally free of snow from mid-June to the end of September. The absence of large herbivores such as caribou and muskox, as well as a high density of snow geese distinguish the trophic structure of Bylot Island from the other tundra communities. The presence of long-term and multispecies monitoring makes Bylot Island a wise choice for ecosystem studies. Material and methodsIt will be necessary to 1) define the food web of Bylot Island tundra with a species resolution 2) delimit and characterize at the biome scale the wintering grounds, the migratory stopover sites and the partial migration areas of migratory and partially migratory species 3) juxtapose the boundaries of wintering and stopover areas on a map of global biomes 4) represent the connectivity through animal migration as a tripartite network (Bylot food web, migratory stopover sites and wintering grounds) 5) create seasonal maps of Bylot Island connectivity with the rest of the world 6) describe and compare the tripartite network of Bylot Island connectivity according to basic network proprieties with and without migrant species. References1.Furey N. B., J. B. Armstrong, D. A. Beauchamp & S. G. Hinch, 2018. Migratory coupling between predators and prey. Nat. Ecol. Evol. 2: 1846–1853. 2.Bauer S.