Long-term monitoring of breeding activity of avian predators on Bylot Island, Nunavut

• Main Authors: Gauthier, Gilles, Cadieux, Marie-Christine, Centre D'études Nordiques
• Format: Dataset
• Language: English
• Published: Canadian Cryospheric Information Network 2015
• Subjects: Bylot Island; Glaucous gull; Jaegers; Long-tailed jaeger; Nesting; Parasitic jaeger; Reproductive phenology; Reproductive success; Rough-legged hawk; Snowy owl; Arctic Development and Adaptation to Permafrost in Transition; ArcticNet Network of Centres of Excellence of Canada; Circumpolar Biodiversity Monitoring Program, Conservation of Arctic Flora and Fauna - Terrestrial; International Polar Year-Arctic Wildlife Observatories Linking Vulnerable EcoSystems; Polar Knowledge Canada/Canadian High Arctic Research Station; Arctic; Nunavut; Canada; ArcticNet; Circumpolar biodiversity monitoring program; Conservation of Arctic Flora and Fauna; Glaucous Gull; International Polar Year; Long-tailed Jaeger; Parasitic Jaeger; permafrost; snowy owl; Tundra
• Online Access: https://dx.doi.org/10.5443/623; https://www.polardata.ca/pdcsearch/?doi_id=623

We are monitoring the nesting activity of Long-tailed Jaegers, Parasitic Jaegers, Glaucous Gulls, Snowy Owls and Rough-legged Hawks. We find nests through either systematic searches or opportunistically. All nests found are positioned with a GPS and revisited during the breeding period to determine laying date, clutch size, hatching date and fledging success. We also study their diet by collecting regurgitation pellets and prey remains at nests (2004-2008) and blood samples from adults and young for isotopic analysis (2007-2010, 2014). Abundance of these birds is also determine using visual counts from a vantage point (since 2004) and line transects (since 2007). For a sample of nests, young are banded at the nest, and occasionally adults as well. We also marked Snowy owls with satellite transmitters (2007, 2014) to track their migratory movements over a 2-year period. Automatic cameras are installed at some nests to monitor the activities and behaviour of these bird species. : Purpose: Predators may play a key role in the functioning of arctic tundra ecosystems and could potentially control the abundance of their prey. Avian predators, mostly raptors and seabirds, are the most diverse groups of predators in the Arctic and range from highly specialists to highly generalists. Measuring annual variation in their abundance is thus essential to understand trophic interactions in the tundra. Annual reproductive success sets the stage for an individual's contribution to the gene pool and is one of the determinants of population growth (or decline). It is governed by a depreciative process that starts with an initial investment of eggs and ends (from a northern perspective) with the fledging of young and their movement south during migration. The depreciation involves a cascade of interactions with the habitat (e.g. quantity and quality of forage), competitors, predators and parasites. In many areas, predation is the leading cause of nesting failure in birds, and thus nesting success is a major component of predator-prey interactions. Quantifying the annual variation in their diet (through blood samples or regurgitation pellets) according to the availability of their prey will also help us better understand trophic interactions in the tundra. : Summary: Not Applicable