WOODCOCK SINGING GROUND COUNTS IN CENTRAL NORTHERN STATES IN 1952 
John W. Aldrich 
U. S. Fish and Wildlife Service 
For the second year singing ground counts of woodcock were made by 
cooperators in the central northern states of Minnesota, Wisconsin and 
Michigan. The results for both years are shown in tabular form in terms 
of singing grounds per 10 miles of route. The figure used as an index 
of the number of singing grounds for each group was the highest number 
recorded of two or more counts during the month of May. April counts 
are now disregarded because of demonstrated fluctuations due to move-~ 
ments of birds during that month. A minimum of two counts was consider- 
ed necessary to give a satisfactory sample of the birds present. The 
number of singing grounds (Table 1) was converted to the number per 
unit length of route so that routes of different lengths could be com=- 
pared with one another. 
It will be noted that in the table two methods were used in com- 
paring results of 1951 with 1952: (1) counts made only on routes which 
were covered in both years and (2) average number of birds per 10 miles 
of route heard on all trips each year. It is believed that a compari- 
son of counts made over the same route in different years is mre 
reliable than average numbers for all routes, many of which are in 
different locations in the two years. For this reason it was a little 
disappointing that in only six instances out of a total of 19 counts 
made this year, were they over the same routes as last year. It will 
be noted also that these 6 comparable counts showed a 13 percent de- 
crease in woodcock singing grounds whereas the average figures based 
on all counts showed a 21 percent decrease. It is not known at the 
present time whether either of these figures is significant because 
no thorough check has been made of the statistical reliability of these 
data. We are, however, making an effort to have similar data, collect- 
ed over many years in other parts of the country, analyzed by statisti- 
cians. Next year it is hoped that we will be in a much better position 
to plan our woodcock singing ground investigations so that the data ob- 
tained will be of known statistical reliability. 
We wish to express thanks to the Minnesota, Michigan and Wisconsin 
Departments of Conservation for their cooperation in this wrk. Partic- 
ularly we are appreciative of the cooperation of the following persons 
who actually participated in the census wrk: Robert I. Benson, Je Ke 
Bronoel, W. D. Burnett, Arnold B. Erickson, Otto Failing, Robert E. 
Farnes, Vernon E. Gunvalson, Gladys A. Hall, Orland L. Haugen, P. Be 
Hofslund, Frank D. Irving, Wm. H. Langley, Don Ledin, Norman J. Ordal, 
Walter L. Palmer, Tony Peterle, Robert R. Rafferty, M. H. Stenlund, 
Ivan Thomson, R. C. Van Etten, and John L. Zorichak. It is hoped that 
they will be in a position to carry on these valuable studies next 
spring. 
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