Molt Migrant Canada Geese in Northern Ontario and Western James Bay

Abstract

We undertook migration monitoring surveys and analysis of long-term banding data to determine if there was a significant premolt movement of Canada geese (Branta canadensis) from restored and reintro duced populations in southern Canada and midcontinent United States into northern Ontario and western James Bay. We examined migration chronology, origins, and demographic characteristics of molt migration of Canada geese in northern Ontario and on Akimiski Island, Northwest Territories. From 1985 to 1989, a conspicuous northward migration of large Canada geese was documented throughout northern Ontario from midMay to the end of June, well after the April migration of the subarctic nesting subspecies of Canada geese (B. c. interior); most nesting interior Canada geese in the Hudson Bay and James Bay lowlands were incubating eggs at this time. Summer-banded Canada geese originating from populations in 26 states and 6 Canadian provinces were captured in coastal areas of James Bay and Hudson Bay between the borders of Quebec and Manitoba. Morphometric discrimination indicated the presence of molting giant Canada geese (B. c. maxima) Most foreign, summer-banded birds were yearlings (53%) and 2-year-olds (17%), but birds up to 15 years old were captured. Approximately 58% of 2-15-year-old females had brood patches, which indicated a nesting attempt in the year of recapture. We suggest that increasing populations of giant Canada geese and declining habitat availability on northern brood-rearing areas will result in increasing levels of competition between populations of Canada geese. Presence of molt migrants on northern breeding areas will also complicate management of some Arctic and subaretic nesting populations of Canada geese.