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For 40 years Wayne Mollhoff conducted a personal bird census every January. He explains:"After having run several Breeding Bird Survey routes, and participated in several Christmas Bird Counts, I became curious to see what might be found on a winter count under the more tightly controlled parameters of a census, as contrasted with Christmas counts done with variable numbers of observers." The count was set up similarly to the USGS Breeding Bird Survey routes with 50 stops, one-half mile (800 meters) apart, all birds counted for 3 minutes, with birds counted at one stop not counted again at following stops. The census route ran from the northwest corner of Boone County, along Beaver Creek, to a point outside Albion. Counts began at local sunrise. A total of 73 species were recorded during the 40-year census. This paper records those results and offers observations on patterns of occurrence or absence and changes in frequency.A Nebraska Ornithologists' Union Occasional Paper
Abonner på vårt nyhetsbrev og få rabatter og inspirasjon til din neste leseopplevelse.
Ved å abonnere godtar du vår personvernerklæring.