44 



Game Survey of the North Central States 



It is therefore of particular significance to find in central Wisconsin a belt 

 of counties, lying between the regular quail range and the nearly quail-less area, 

 which contains few or no quail at the present time, but shows evidence of tem- 

 porary abundance of quail in the past. The degree of fluctuation is so great that 

 the occasional periods of abundance may be called "irruptions." The location of 

 the irruptive area and of the observers in it are shown on Map 7. The nature of 

 the evidence on "irruptions" appears in Table 9- 



TABLE 9. Evidence of temporary abundance of quail in the "irruptive" area 



The irruptions most strongly supported by evidence are one in 1916 in central 

 Wisconsin,~and one in 1897 following the Hinckley fire in Minnesota. The 1916 

 irruption immediately preceded the killing winter of 1917-18. The best assump- 

 tion is that this, as well as other irruptions, was terminated by killing winters. 

 This assumption is further corroborated by the greatly varying length of the period 

 of abundance, which the table shows to have been from one to four years. 



