Blood lead concentrations of juvenile American black ducks (Anas rubripes) sampled in unhunted sanctuaries of Nova Scotia (NS) and Prince Edward Island (PEI), Canada, usually were <30 parts per billion (ppb). Based on gizzard content analyses of juvenile American black ducks from hunted areas, eight (24%) of 33 flightless birds contained ingested lead shot. Blood lead concentrations were ≥100 ppb in seven of eight juveniles with ingested shot; thus we adopted blood lead concentrations 100 ppb as our threshold indicating exposure to non-background lead. The proportion of both American black ducks and ring-necked ducks (Aythya collaris) with elevated blood lead concentrations (>100 ppb) exceeded 5% in hunted areas sampled in NS and PEI combined. The Canadian Wildlife Service draft policy is to consider replacing lead shot with non-toxic shot for waterfowl and snipe hunting if 5% of American black ducks exceed a blood lead concentration of 200 ppb. American black ducks significantly (P < 0.05) exceeded this threshold but ring-necked ducks did not. The source of lead in hunted areas may have been lead shot; we recommend that it be eliminated and replaced by an acceptable non-toxic shot for waterfowl hunting. Twenty four (96%) of 25 of American black ducks overwintering in Sullivans Pond, Dartmouth, NS, contained elevated (>100 ppb) blood lead concentrations and 19 (76%) had detrimental concentrations (>200 ppb). We believe that the source of lead at Sullivans Pond was automobile emissions.

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