144 



Game Survey of the North Central States 



chart) . Thus in 1920 five observers report ruffed grouse as very abundant, and 

 two observers report prairie chicken as very abundant. In the same year 22 report 

 ruffed grouse as fairly numerous, while seven report chickens as fairly numerous. 

 The most frequent report of ruffed grouse is "fairly numerous" whereas the 

 "most frequent" report for chickens is "scarce," hence the curves for the two 

 species start at these two points. 



LAST CYCLE IN WISCONSIN 



AS REPORTED BY STATE GAME OBSERVERS 



STATUS 



NO. OF OBSERVERS 

 1920 1921 1922 



1923 1924 1925 1926 1927 1928 1929 *I930 



VERY ABUNDANT 



ABUNDANT 



FAIRLY NUMEROUS^ 



SCARCE 



VERY SCARCE 



TOTAL NUMBER 

 OBSERVERS 



All figures on right 

 are prairie chicken 



All figures on left 

 ore ruffed grouse 



90% of observations are 

 within the hatched zone 



PRAIRIE CHICKEN^ 



50 



Curves are weighted means . Letch point calculated as follows: starting 

 with most frequent abundance class, multiply next above by I, next by 2, nexr 

 by 3 etc. Add; divide by 4. Same for classes below. Subtract weight above 

 from weight below. This gives departure from most frequent class. 

 -$- Very few reports covered 1930, hence dafa disregarded. 



CHART 9 



The hatched zone includes roughly 90 per cent of the total number of ob- 

 servations for each year. The hatched zone, in effect, indicates 90 per cent of the 

 total lag shown hypothetically in Section H of Chart 8, but as determined by an 

 investigation entirely independent of the game survey on which Chart 8 is based. 



Map 12: This map gives some of the geographic locations from which 

 Grange and the author obtained the data on the last cycle which are summarized 

 in Charts 7, 8, and Map 12. 



