U.S. Department of Agriculture: Animal and Plant Health Inspection Service


Date of this Version

July 2003


Published by Wildlife Society Bulletin 2003,31(1):265-269.


In many localities, Canada geese (Branta canadensis) have habituated to urban settings and their populations are increasing. Reproductive inhibitors contained in synthetic grit could play a role in integrated Canada goose management. We describe and quantity the physical characteristics of natural grit collected from the gizzards of Canada geese from 4 regions of the United States. The average grit sample had a weight of 14.26 g, a volume of 2.45 ml, a grit-particle count of 1,419, and a soil weight of 6.85 g. The average grit particle measured 2.02 mm long and 1.52 mm wide, and had an area of 2.05 mm2 and a roundness rating of 1.25. Synthetic grit could be patterned after our findings to most likely be retained and utilized in the gizzards of Canada geese.