Relative Distribution of Mallard and Black Duck in Winter
Citations
49 citations
Cites background from "Relative Distribution of Mallard an..."
...Table 1 presents an updated version of the information presented earlier (Wing, 1943; Johnsgard, 1961b), summarizing Audubon Christmas Count information on Mallards and Black Ducks in the Johnsgard in American Midland Naturalist (January 1967) 77(1)....
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...State-wide Mallard: Black Duck ratios for the- first 40 years, from 1900 to 1939, were first calculated by Wing (1943), and provide an estimate of relative state wintering-ground distributions for this period....
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...Table 1 presents an updated version of the information presented earlier (Wing, 1943; Johnsgard, 1961b), summarizing Audubon Christmas Count information on Mallards and Black Ducks in the...
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32 citations
11 citations
Cites background from "Relative Distribution of Mallard an..."
...Wing (1943) became interested in the ratios of Mallards to Black Ducks throughout he eastern states before the range shift was at all apparent, and calculated state ratios for the two forms on the basis of the data provided by the annual Audubon Society Christmas counts for the forty years 1900 to,…...
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3 citations
Cites background from "Relative Distribution of Mallard an..."
...The mallard range, initially restricted to the central northern prairies, had been expanding into the range of the east coast black duck since at least the 1940s [22, 23]....
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