INFLUENCE OF DENSITY ON GROWTH OF WHITE-TAILED DEER

Age and mass data from 9,956 white-tailed deer (Odocoileus virginianus) from South Carolina were used to examine the relationship between growth patterns of each sex and population density. Growth parameters for 16 annual cohorts born between 1965 and 1981 were derived with a Richards function; population sizes were estimated with a competing risks model. There were significant relationships of growth parameters for males, but not for females, with population density. Males grew more slowly and reached smaller adult masses at the highest population densities. The growth-density association was weakest in young deer and strongest in males 1.5-2.5 years of age. Sex-specific differences in the growth-density relationship may be due to energetic costs associated with competition among males for mates or to a higher use of marginal habitats by males than by females. One consequence of sex-specific relationships of density with growth rates and adult size is a decrease in sexual dimorphism in size at greater population densities.