A dynamic white-tailed deer population simulator and lessons from its use

Abstract

From data and concepts in the literature, DEER, a FORTRAN IV program that operates on an IBM 370/65 computer, was written. The general purpose population simulator was designed for managers of white-tailed deer (Odocoileus virginianus). It is based on a dynamic age and sex-specific algorithm, unifying bioenergetic, sociological, hunter, and population characteristics.

The system determines a management plan that will stabilize a population under the conditions specified. The system is also designed to be used for examining deer populations and for educating students on wildlife ecology and management.

The concept that achieving a constant sex ratio can be used to stabilize a population was explored. The results indicate that a population will stabilize with any sex ratio when all management activities are oriented toward achieving such a sex ratio. An increase in the proportion of doe deer in the herd results in an increase in the allowable harvest but causes a decrease in the ratio of the antlered(trophy)-to-antlerless deer changes with a population natality change. A static management strategy (e.g. to achieve a constant ratio of antlered-to-antlerless deer) results in unstable (and probably suboptimal) harvest when the reproductive rate, adult sex ratio, and fawn sex ratios are dynamic. DEER is a decision aid useful for replacing rule-of-thumb management.