As an aid to biological interpretations of the relation- 

 ships between land use and pheasant abundance in Illi- 

 nois, the data were analyzed for statistical significance 

 on an IBM 7090 digital computer; the mathematics in- 

 volved a multiple regression analysis by the least squares 

 method. 



Test statistics included 10 independent variables in- 

 \ oKing land use (Table 1 ) and three dependent variables 

 involving pheasant abundance. Indices of abundance 

 were based on the mean number of pheasants observed 

 by rural mail carriers per 100 miles of driving in Illinois 

 counties during si.x counts in 1957 and 1958 (Table 1). 



Table 1.— Abundance of pheasants in relation to land-use practices in Illinois counties. Abundance for each county within the 

 pheasant range was determined by calculating the mean number of pheasants reported by rural mail carriers per 100 miles of 

 driving during six 5-day census periods, 1957 and 1958. All counties of the state were included in the first census; 28 southern 

 counties (75—102 below) in which no pheasants were reported were not included in later cenususes. 



