The formal idea that populations are ultimately 

 controlled by food probably began with the writings of 

 Malthus, first published in 1798 (Davis 1950). Davis (1950), 

 from the perspective of game management, stated: "Our modern 

 game managers have ample evidence that inadeguate food 

 supplies render a species susceptible to various mortality 

 factors." Malthus noted that an epidemic is followed by 

 healthfulness because the weak are killed, and there is more 

 room and food for the survivors. This concept has been 

 applied by wildlife biologists to the effect of predators on 

 their prey populations. 



Although gualif ications are often given, the idea that 

 food can be, and ultimately is, the factor limiting ungulate 

 populations is basic to most comprehensive publications 

 relating to wildlife management (Leopold 1933, Lack 1954, 

 Dasmann 1971, Caughley 1976b and 1977, and McCullough 1979). 

 Theories of density-dependence and compensatory mortality and 

 reproduction rely on the implicit assumption that food and/or 

 space are limiting the population and that mortality varies 

 directly with forage-nutrition levels. Caughley (1977) 

 states: "Should the (population) decline be a consequence of 

 reduced food supply or poor habitat the diagnostic feature is 

 a rise in juvenile mortality, usually coupled with a decline 

 in juvenile fecundity." 



More recently, Peek (1980) summarized current management 

 philosophy as follows: 



"Very often resource management is based on an 

 unrecognized underlying hypothesis. In the case of 

 native ungulates, the hypothesis that a weather-forage 

 complex regulates populations is implicit in much habitat 

 and population manipulation. The alternative — that 

 predation controls populations — is widely accepted 

 also. " 



Data collected during this study enabled us to examine 

 the relationships among fawn mortality, predation, forage 

 production and deer condition, winter severity, and deer 

 density. 



Fawn Mortality In Relation To Forage Production 



Multiple regression analysis indicated that fawn survival 

 to December was related to the same factors which were highly 

 predictive of forage production: precipitation from July 

 through April prior to the growing season, and mean 

 temperature during May (see Chapter 3). Thus, we substituted 

 July-April precipitation and mean May temperature for forage 

 production estimates, to compute regressions relating fawn 

 survival to forage production annually from 1960 to 1986. 



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