Source of Data 
During March, April, and May of 1962, cooperators in 20 
eastern and central States and 4 eastern Canadian Provinces 
made counts on 329 routes. Most routes were covered on approx- 
imately the same dates as in 1961. Population change from 1961 
to 1962 was determined from counts made on 263 routes covered 
in both years (comparable routes). A total of 148 comparable 
routes was available for analysis in the Eastern Region (a 
decrease of 2 from last year), while the number of comparable 
routes increased from 73 to 115 in the Western Region (an 
increase of 42). In addition to the routes covered both years, 
21 new routes were run in the Eastern Region and 18 in the 
Western Region during the 1962 survey. These routes will 
strengthen the survey since they can be used to compare 1963 
populations with those of 1962, assuming they are covered 
again. 
Method of Analysis 
Survey data of previous years have been analysed in two 
ways to yield indexes of woodcock abundance: the number of 
woodcock heard per stop, and the number of woodcock heard per 
route. Although Robbins (Woodcock Newsletters: No. 1, 1958; 
No. 2, 1959) has shown that both values yield approximately 
the same results in terms of year-to-year changes in relative 
population levels, the number of birds per route is believed 
to be preferable because the count for each route then is 
given weight in proportion to the number of woodcock present. 
The use of average number of birds per stop would give each 
route equal weight, even though some routes represent many 
more stops and much more habitat than others. Listening 
points are located in suitable breeding habitat, and all of 
them on a route must be covered during a period of about 35 
minutes. Thus, routes with the most stops occur in more 
continuous breeding habitat and counts on these routes could 
be expected to be higher than on routes with a few stops 
located in a limited amount of suitable cover where much of 
the available listening time is spent in driving between 
stops. 
Adjustments of the data were made for routes that did 
not have the same number of stops each year. Data for the 
year with the larger number of stops were reduced to make 
them comparable to those for the year with the smaller number 
-2~- 
