S62 I LI CTU AT urns / V GROUSE ABUNDANCE 



iiiiusuul scarcity of llic birds aliuut once in eight years, and lliat tliis has occurred three 

 times in his cxperieiRe of thirl\ )fars".'" In 1918 Burnham' concluded that, in recent years, 

 shortages of grouse had recurred at about lU-year intervals. Hut it was the scarcity of 1926- 

 29 that really stimulated study of this phase of the problem, although a sharp loss of produc- 

 tivity in 1924, especially in parts of the .Northeast, had resulted in the formation by the .Amer- 

 ican Game Protective Association of a Grouse Inxestigation Committee and its subsidiary the 

 New England Grouse Investigation Committee. Since that lime a number of workers have com- 

 piled information indicating, for their respective regions, what the trend of grouse abundance 

 has been. The principal accounts of this kind are those of Leopold"', Clarke"*, Bump"", 

 Grange' ', Foote"", Tubbs'"', and Wing"', and, although the data are more or less indefinite 

 prior to the turn of the century, they do reveal that a major decline and recovery took place 

 throughout most of the range of the species during each decade between 1900 and 1940. 



These regional accounts together with supplemental data, both contemporary and more 

 recent, derived from State and Provincial reports, personal correspondence with State and 

 Provincial officials, wildlife journals, and sporting periodicals furnish a background against 

 which to interpret the data of the present Investigation. In assembling this material, however, 

 it has been found that different statements for the same region often fail to agree regarding 

 specific years. For this reason it has been difficult to determine in some instances just when 

 the high and low points of grouse abundance were reached, although the occurrence of scarcity 

 can be plotted more definitely because it has always caused greater concern. Another feature 

 is the fact that fluctuations have seldom followed a smooth curve. Rather than rising and 

 falling steadily between 1-year peaks and troughs, the trend of abundance has exhibited high 

 and low levels which have usually lasted from two to four years and which have themselves 

 often been characterized by considerable variation. Nevertheless the data can be correlated 

 sufficiently to permit defining within narrow limits the intervals which have occurred in recent 

 years between periods of abundance and of scarcity (figure 59). 



In New York the records leave no doubt that grouse abundance over most of the State 

 reached a low ebb in 1907"", 1917^ and 1927\ Moreover there is a general agreement in 

 these dates throughout the Northeast, although the decline of the late '20s apparently took 

 place a year or two earlier in New England'^ and the Maritime Provinces', and a year later in 

 Pennsylvania". There is also evidence of less severe reductions in 1903"° and 1924*" and 

 some indication is to be found of scarcity during the late '90s. Omitting these minor "lows", 

 however, there has been a remarkable regularity in the spacing of the other periods at inter- 

 vals of nine to ten years. 



But since the low period which began in 1927 no comparable widespread scarcity has 

 occurred in New York although there was a minor depression in 1936-37, apparently similar 

 to those of 1903 and 1924. Yet more pronounced declines in grouse abundance were re- 

 ported during the years 1934-36 in other sections of the Northeast'"' '■^. During this period 

 all of New England and eastern Canada were affected. In fact, in 1936 the open season in 

 Massachusetts was curtailed on this account"". \^'here these declines occurred they followed the 

 preceding lows by intervals of eight to ten years. Moreover, the same was true of the minor 

 depression of 1936 in New York. 



Summarizing his data for Ontario, Clarke'* recognized diminutions among ruffed grouse 

 during the years "19.3.3-4 (and 193.S presumed I ; 1924-.S: 1914-6: 1904-.5-6; 1894-.S; 1883-4-5: 

 1874" indicating an average period of "between nine and ten years". 



* SuleniPiil maJe ia 1908. 



A Pertooal correipoadcnce with State and Proviorial official*. 



