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by
Jean Rodrigue, Jack Hughes and Michel Mélançon
Bird banding is a technique used by ornithologists that provides useful information on migration. Birds are caught and a numbered band is placed on one
of their legs. Data from recovered bands tell us about birds’ distribution and movements of various avian species, life span and causes of mortality. Biologists use this information to monitor and manage bird
populations.
Between 1917 and 1997, 23 109 Canada Geese were banded in four major regions of Québec. These regions were the eastern shore of Hudson Bay, Ungava Bay,
James Bay and southern Québec (Figure 1). The majority of these birds were banded in northern Québec: 11 662 of them along the eastern shore of Hudson Bay and 10 508 in Ungava Bay.
The general migratory pattern of the Canada Geese banded in Québec shows that they winter on the east coast of the United States (Figures 2 to 4),
making them part of what is called the Atlantic population.
Two migratory patterns have been observed in the Canada Geese of Hudson Bay (Figure 2); they use either the Atlantic or the Mississippi Flyway.
However, birds born in this region use only the Atlantic Flyway for migration, and the presence there of birds from the Mississippi Flyway indicates that the eastern shore of Hudson Bay serves as a moulting area
too.
In Ungava Bay (Figure 3), only one migratory pattern has been observed, though the region may be used for moulting by other populations. This could be
due the proportion of adults among banded birds which was 57% as opposed to 80% for Hudson Bay. One can therefore assume that most of the birds banded in Ungava Bay belonged to family groups, given that the ratio of
young to adults was almost one-to-one (or 50%), which is the proportion found in breeding studies. Another reason only one migratory pattern was observed is that only Atlantic Flyway moult-migrants use Ungava Bay.
Some moult-migrant geese have been captured in Ungava Bay during recent banding operations, and all of these were from Resident Canada goose population in the Atlantic Flyway. It would be interesting to band
moulting adult Canada Geese in Ungava Bay to see if this region is used as a moulting area by other populations.
Canada Geese banded in James Bay and southern Québec migrate within the Atlantic Flyway (Figure 4). However, most of those in southern Québec are
considered to constitute a resident Canada Goose population.
Atlantic Flyway Canada geese are banded annually in northen Québec (near Povungnituk and near Kuujjuaq), in southern Québec and at several locations in
the United States.
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