Johnsgard, "Half-century of Winter Bird Surveys at Lincoln and Scottsbluff, Nebraska," from Nebraska Bird Review (September 1998) 66(3).
Since 1900, the National Audubon Society has sponsored annual "Christmas bird counts" during the two-week period encompassing Christmas; and as a result, long-term data on winter bird populations have accumulated, especially for some locations. The first two such counts in Nebraska were made in 1909 and in 1912 in Lincoln. While similar counts were made in Omaha from 1909 to 1911, no further counts were conducted elsewhere in the state until the 1940's. Beginning in 1947 and continuing to the present, an unbroken series of counts were made in Lincoln, usually by members of the University Place Bird Club, the Audubon Naturalist's Club, or the Wachiska chapter of the National Audubon Society. Omaha counts were re-initiated in 1944 and, except for a gap from 1955 to 1961, have also continued to the present. The only other long-term series of counts comes from Scottsbluff where an unbroken set of counts extends from 1949 to the present.
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