The Game Cycle: A Challenge to Science and a
Threat to Sport
1R. T. King and 2Aldo Leopold
What is the Game Cycle?
All of the grouse and some of the rabbits of the northern hemi-
sphere experience periods of extreme scarcity, alternating witb Deriods of
abundance. This fluctuation has come to be known as the grame cycle. The
proprietyof this apellation will be discussed later.
There are   _    species of grouse in North America. Of these the
ruffed grouse, and the pinnathd grouse or prairie chicken, are the most
imnortatn by reason of their wide distribution and the high esteeem in which
they are held as game birds. Both are now known to be subject to cyclic
fluctuation. It is also certain the sharptail grouse, ptarmigan, and blue
grouse are subject to the cycle. In all probability sage hens, soruce
grouse, Franklin's grouse, and the other minor species are affected. If
this proves to be the case, it means that over half of the upland game
bird species of North America periodically disappear.
It also appears that the red grouse and black grouse of Europe
experience cyclic fluctuation, and possibly to some extent the Pray or
Hungarian partridge. Fluctuations of some sort are known to exist in the
sand grouse of Siberia. The indications are that quail, cheasants and
pigeons are the only American genera exemot from this phenomenon which en-
circles the northern half of the globe.
Both of the authors, and at least a dozen other investigators in
the United States and Canada, are collecting evidence on the behavior of
1Research Fellow, University of Minnesota, in coo-er tion Aith the U. S.
Biological Survey..
21n Charge, Game Survey, Sporting Arms & Ammunition Mfgrs. Institute.