forage that is inadequate in quality to increase the condition 

 of any deer. 



Physical condition of females can also decline because of 

 reproductive drain unrelated to increased intraspecif ic 

 competition for food. This scenario can occur even over a 

 long series of years of relatively good forage quality, but is 

 especially likely to occur when a series of good years is 

 followed (as is often the case) by a very bad year. All 

 females are more vulnerable than usual to mortality and low 

 productivity when a very dry year occurs, but those which had 

 been most productive in previous years are most vulnerable. 

 Thus, poor female condition following extended periods of high 

 productivity can explain both the unusually high female 

 mortality that occurred during winters 1964-65, 1971-72, 

 1983-84, and 1984-85 and the low fawn recruitment observed 

 during the following summers. Fawn recruitment was generally 

 high to weaning during the prior years of 1963-64, 1967-70, 

 and 1977-83, respectively. 



Often, recruitment remained relatively high during the 

 first year of poor forage following good years. That occurred 

 because, when current forage conditions were not extremely 

 bad, females can rear 1 more fawn crop by utilizing body 

 reserves. This, however, only leads to further deterioration 

 in body condition, even poorer fawn recruitment, and increased 

 adult female mortality the following year. 



Although superficially, these condition cycles often 

 appeared to coincide with changes in density, density and 

 intraspecif ic competition for food were not the operative 

 factors. Physical condition of females that successfully 

 recruited fawns declined even during what were considered good 

 forage quality years with low deer density on our study area. 

 A decline in recruitment, often drastic, is triggered by a 

 cumulative decline in female condition and/or an abrupt change 

 in forage quality unrelated to an increase in deer density. 

 Condition cycles in adult females are more related to density- 

 independent changes in quality of forage and cumulative fawn 

 recruitment rates than to deer density and forage quantity . 



Increases in deer density result because fawn survival 

 increases and adult mortality decreases relative to previous 

 levels. Random variation of environmental conditions can 

 result in patterns of fawn recruitment that will mimic what 

 has been viewed as density-dependent recruitment. By random 

 chance, a good fawn recruitment year or series of years is 

 most likely to be followed by at least 1 year somewhat worse 

 than the good year(s). Fawn-rearing conditions can vary 

 considerably across a spectrum, but generally fall within 

 certain limits, depending on environmental variation in the 

 area. Extremely wide environmental fluctuation does not 



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