We examined the prevalence of lead exposure from ingestion of waste lead shot among age and sex cohorts of Canada geese (Branta canadensis) on the breeding, migration, and wintering grounds of the Eastern Prairie Population. Blood samples from 6963 geese were assayed for lead concentration by atomic absorption spectrophotometry. On the breeding grounds, no goslings and <1% of adults showed evidence of recent exposure to lead shot (i.e., concentrations in the blood elevated above the threshold value of 0.18 ppm lead). However, median background blood lead concentrations (i.e., blood samples with