Introduction
Poisoning of waterfowl by lead shot has been the subject of a number of studies in North America (Sanderson and Bellrose 1986). Shifts to alternative cartridge types were motivated in part by the risks of lead poisoning in waterfowl that ingest spent shot. This change is the logical corollary to the action taken by governments for several years past to reduce releases of lead into the environment (e.g., banning lead additives in gasoline, setting industry standards).
In 1991, certain areas in Canada were designated non-toxic zones; i.e., the use of lead shot for the hunting of migratory birds was banned there. In 1997, Canada implemented a nation-wide ban on the use of lead shot for hunting waterfowl within 200 m of a watercourse, though lead pellets were still allowed in cartridges used to hunt in farm fields until 1 September 1999. After that date non-toxic shot is required nationally for migratory game birds, except for American Woodcock Scolopax minor, Band-tailed Pigeons Columba fasciata, and Mourning Doves Zenaida macroura.
Though a number of studies on lead shot have been undertaken, there is still little information on the springtime prevalence of shot in waterfowl. We hope that this contribution will add some knowledge of the incidence of lead shot in a species hunted by aboriginal people in spring, namely the Canada Goose Branta canadensis. Dickson (1996) reports that this species' numbers have declined in eastern North America in recent years, though an increase of the Atlantic population of Canada Geese has been observed since recreational hunting was closed in 1995 (Harvey and Rodrigue 1998).
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