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sample check areas represent the better types of habitat within their respective 
locations in the State. The censuses were made by boat over established routes: 
(Boat Surveys) 
Year Lineal miles censused Potential breeders per 
lineal mile 
1949 85 ' 6.80 
1950 81 7.91 
1951 120 8.18 
1952 82 7.13 
Judging from this information, Michigan had a good population of potential 
breeding stock, approximately equal to the four-year average. Production during 
each of these years was considered good. 
In addition to the previously conducted surveys to determine potential 
breeding populations a "pilot study'' was made to test the aerial transect method 
advocated by the U. S. Fish and Wildlife Service. The objective of this technique 
is to obtain a quantitative population index of breeding pairs per square mile for 
each of the four major biotic zones (strata) of the State. 
This type of survey has proven successful in the Prairie Provinces and with 
some modifications has been used with a fair degree of success in the Eastern 
Seaboard States and Maritime Provinces. Since habitat conditions in Michigan are 
somewhat similar to those in some of the Eastern States, an attempt to use the 
method appears justified. 
In cooperation with Fish and Wildlife Service personnel a sampling plan was 
worked out that provided for an optimum sampling ratio based on the best available 
information. This plan was executed and the results are summarized in Figure 2. 
The results were not entirely satisfactory but from the experience pained 
through this ''pilot study" we believe that with modifications, this technique may be 
applied to limited portions of the State to obtain indexes of breeding populations. 
The low index values shown for the northern half of the State suggest that further 
aerial censuses may not be justified. 
Nesting Conditions 
Weather conditions were favorable during the nesting period. May temperatures 
were normal with precipitation slightly below average. In June, temperatures were 
above normal, Precipitation was above average in the northern half of the State and 
below average in the south. With the exception of a border of habitat along the Great 
Lakes shoreline, nesting conditions in Michigan appeared to be favorable for a 
successful hatch. 
Along the Great Lakes, former nesting habitat has been inundated as a result 
of extremely high water levels. The net effect of this flooding is not entirely clear, 
but field observations and the results of brood studies indicate that production in 
general has not been seriously hampered. 
