Observations on a 40-Year January Bird Census in Boone County, Nebraska, 1978-2017 - Wayne Mollhoff - Bog

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