In 1919, local birder Allen Frost suggested to Maunsell Crosby
that an annual May Census be conducted in Dutchess County. Crosby
held the census each year until his death in 1931, after which Allen
Frost continued until his own death in 1946. At this point, Dutchess
County bird records were passed to Ralph T. Waterman, who then continued
the census with his son Otis. Subsequently, the bird club that Mr.
Waterman founded in 1958 assumed responsibility for Dutchess County
records, including the May Census. Each year, usually on the weekend
closest to May 15th, teams of birders fan out across the county
to count all the birds they see. The results of the census, along
with other records, can then be analyzed to identify population
trends and provide evidence of the impact of environmental changes
in the area.