State of the State’s Deer Herd
Last month we discussed the 2012 hemorrhagic disease (HD) outbreak [July; Page 24]. This month we will explain how HD and other factors affect deer populations in Missouri. A deer population increases or decreases based on the difference in birth (fecundity) and death (mortality) rates, which are often influenced by regulations, forage availability (i.e., acorns), predator abundance, and disease outbreaks.
Antler Point Restriction
The primary goal of the antler point restriction (APR) was to lower deer densities by increasing doe harvest, not to increase buck age structure. The two might seem unrelated, but often hunters resort to harvesting a doe when they have to pass on young bucks that do not meet the APR. The increased doe harvest yields lower deer densities over time, but also increases buck age structure, as younger bucks are often protected from harvest by the APR. Since the APR has been shown to decrease deer density, at this time it is not biologically or socially acceptable to expand the APR statewide, as deer populations in many southern counties are currently at or below desirable levels and unable to sustain increased doe harvest.
After the APR is implemented, doe and button-buck harvests tend to increase and antlered-buck harvest decreases as hunters fill permits with antlerless deer when unable to harvest a legal buck. As a result, buck survival increases, allowing them to mature into older age classes. As more bucks are recruited into older age classes, buck harvest again increases after the initial implementation of the APR. Additionally, over time, doe harvest is predicted to decrease as deer populations are reduced and does compose a smaller proportion of the population.
Antlerless Permits and Season
The intended purpose of antlerless permits and season is to allow hunters the flexibility to manage deer populations and address deer issues, while providing additional hunting opportunity. However, there is a misperception that when “any number” of antlerless permits are available the population can sustain high doe harvest. A harvest of approximately 20–25 percent of the adult doe population will keep the population stable, any more and the population will decrease, and any less will lead to population increases (see A Deer Harvest Scenario).
Acorn production can have a substantial effect on deer populations in forest-dominated areas, like southern Missouri. In heavily forested (more than 50 percent) landscapes, acorns compose the majority of a deer’s fall and winter diet. However,