November, IQ44 



Bellrose: Duck Populations and Kill 



343 



Table 3. — Per cent of entire fall flight, per cent of total bag, and mortality quotient 

 (indicating relative mortality from hunters) for each of the important duck species 



or groups in the Illinois River valley, 1938. 



Species* 



Per Cent of 



Flight During 



Entire Fall 



Per Cent of 



Total 



Bag 



Mortality 

 Quotient 



Mallard and black duck 



Pintail 



Green-winged teal 



Blue-winged teal 



Widgeon 



Gadwall 



Shoveler 



Lesser scaup 



Canvasback 



Ruddv duck 



94 

 1 

 

 

 

 



61 

 44 

 10 

 35 

 30 

 06 

 0.02 

 3.01 

 0.07 

 0.04 



57.07 

 12.76 



54 

 35 



7.27 



.27 

 .43 

 .48 

 0.40 

 0.43 



2. 

 2. 

 4. 



0.60 

 8.86 



95.40 

 9.57 



24.23 



37.83 



121.50 



1.49 



5.71 



10.75 



100.00 



100.00 



*Certain species omitted because of lack of sufficient data. 



than-usual hunting pressure. Compara- 

 tive figures show that hunting pressure 

 on the widgeon was least in 1940 and 

 1942, table 8; in those years the widgeon 

 population in the Illinois River valley 

 was relatively high, tables 3-7. 



The gadwall, which appears to be 

 similar to the widgeon in most habits, 

 including wariness, was subject to 

 about three times as much shooting 

 pressure. This disparity existed be- 

 cause more of the gadwall flights than 

 ot the widgeon flights occurred during 

 the hunting seasons, figs. 11-15. The 

 seasons of 1939 and 1940, which ended 

 before the gadwall flight had passed 



through the Illinois River valley, were 

 marked by shooting pressures that were 

 comparatively low for this species, 

 table 8. There is no apparent reason 

 for the comparatively low pressure in 

 1942. 



In calculating the kill of the widgeon 

 and the gadwall, it was necessary to 

 begin with the total kill of the two 

 species for 1938 through 1940 as re- 

 ported by duck clubs; hunters often 

 placed widgeons in the gadwall column. 

 An attempt was then made to correct 

 this error through use ol data obtained 

 from our own inspecting of hunters' 

 bags to determine the ratio between the 



Table 4. — Per cent of entire fall flight, per cent of total bag, and mortality quotient 

 (indicating relative mortality from hunters) for each of the important duck species 



or groups in the Illinois River valley, 1939. 



*Certain species omitted because of lack of sufficient data. 



