Ecology of migration

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I propose to use novel, regional-scale automated telemetry arrays to study the movement ecology of blackpoll warblers in Nova Scotia. Blackpoll warblers undertake the longest known non-stop migration route of any small bird, traversing thousands of kilometres of open ocean during a single migratory flight. These warblers undertake these flights from the northeastern United States and adjacent parts of Canada during September and October. The species breeds in areas of coastal Nova Scotia, and throughout the Boreal forest as far west as Alaska. In this research project I will study the movement behaviours of blackpoll warblers in Nova Scotia from the end of their breeding season (post-breeding and juvenile dispersal) through to the end of the migratory period. Blackpoll warblers (and other species of small songbirds) undertake 'landscape-scale stopover movements' during migration -- movements of up to 30 km from their site of initial capture that do not appear to be true migratory flights. These movements appear similar in some ways to movements made by juveniles shortly after fledging. Using the different populations of blackpoll warblers that move through Nova Scotia, I will study these movements, and using observations and experiments, attempt to understand the reasons for them, and how they influence the local populations of these species. I will do this by using small radio transmitters that can be affixed to individual birds, and an array of a hundred or more automated telemetry receiver stations situated at key locations around the Maritimes and elsewhere in the Gulf of Maine. The receiver stations continuously listen for the tags on individual birds, and record the time and date of all detections of those tags. In that way, I can 'follow' individuals as they move throughout the region. Similar arrays of receivers with antennas that are much more densely placed will be used to follow movements of individuals throughout the day. By examining the habitats that individuals choose to move to or stay in, I can infer why individuals are making particular movement decisions. I will also use colour bands to mark all individuals at each of two locations where the species breeds in Nova Scotia -- the Canso Peninsula and Bon Portage Island. Each year I will capture as many individuals as possible, and affix them with unique colour-coded bands. During subsequent years, all sightings of these colour marked birds will be recorded, which will allow me to measure the probability that individuals survive and return to the same place year after year. I can use that information to assess how the decisions made by individuals in the previous year influence the likelihood that they will survive and return to the same location. The proposed research will exploit the use of automated telemetry arrays for the study of movement of organisms. What we learn from this project can be applied to many other questions in wildlife ecology, conservation and management. Our work will help develop and refine this important tool so that it can be used and exploited by other researchers and practitioners around the world.