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USGS · 5222946

Comparative productivity of American black ducks and mallards nesting on Chesapeake Bay Islands

D.G. Krementz·Daniel B. Stotts·G.W. Pendleton·J.E. Hines·Vernon D. Stotts
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Abstract

The authors estimated laying dates, clutch sizes, and nest success rates of sympatrically breeding populations of American black ducks (Anas rubripes ) and mallards (Anas platyrhynchos ) on Chesapeake Bay islands between 1986 and 1989. Neither average laying date nor clutch size differed between black ducks and mallards. Nest success rates were higher for mallards in 2 of 4 years, but were area dependent.

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D.G. Krementz, Daniel B. Stotts, G.W. Pendleton, J.E. Hines, Vernon D. Stotts. 1992. Comparative productivity of American black ducks and mallards nesting on Chesapeake Bay Islands. https://doi.org/10.1139/z92-035

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