Migration ecology of Sabine's gulls (Xena sabini) from the Canadian high arctic

• Main Author: Davis, Shanti E.
• Format: Thesis
• Language: English
• Published: Memorial University of Newfoundland 2015
• Subjects: Arctic; Pacific
• Online Access: https://research.library.mun.ca/8402/; https://research.library.mun.ca/8402/1/thesis.pdf

Sabine’s gulls are the only Arctic gulls that undertake trans-equatorial migrations between their breeding grounds and offshore wintering areas. I used light-based archival geolocation devices (n = 36) to track Sabine’s gulls from one of their northernmost breeding colonies, on Nasaruvaalik Island in the Canadian High Arctic, to their wintering sites in the Southern Hemisphere. I discovered that birds from Nasaruvaalik Island migrate to both the Pacific and Atlantic wintering areas this species is known to use, with the majority of birds migrating to a restricted area in the Humboldt Current off the coast of Peru and a small portion of the birds migrating to an area in the Benguela Current off the coast of South Africa. I characterized the routes, timing, and distance of Pacific wintering Sabine's gulls. Analysis of the movements of these individuals revealed that Sabine’s gulls exploit highly localized areas of elevated marine productivity along a migration route of more than 28,000 km. I identified the Juan de Fuca Eddy off the southwest coast of Vancouver Island, British Columbia as a critically important foraging area during both north and southbound migration. I also describe the non-stop overland crossing by some birds between the Pacific and Arctic Oceans during northbound migration.