Biology And Management Of White-tailed Deer In Alabama

Deer populations respond to varying mortality rates by decreasing,
increasing, or remaining stable. A deer herd will continue to grow
with annual mortality rates of less than 35 percent. The rate of growth
will depend on how far below 35 percent the annual mortality rate actually
is. For example, an annual mortality rate of 20 percent allows
for rapid population growth while at 30 percent, population growth may
be more gradual. With approximately 35 percent annual mortality, a
population will generally remain stable. With a 40 percent annual
mortality rate, the total population will decline; at rates greater than
40 percent this decline becomes more pronounced. The effect annual
mortality has on a population also depends on how the population is
structured with respect to adult sex ratio and on how the annual mortality
is distributed between both sexes. Reproductive output and
recruitment also influences the net effect of annual mortality rates.
Population models have shown deer herds produce the greatest
sustained yields when maintained at approximately 40 to 80 percent of
the estimated carrying capacity (Downing and Guynn 1985). At these
herd densities, the highest harvest rates may be achieved without compromising
habitat integrity. Reproduction and recruitment will exceed
natural mortality significantly at these levels, thereby providing the
optimum range for a sustained annual harvest of deer. Studies have
shown peak harvest rates are achieved at deer densities of 50 to 60
percent of carrying capacity (Downing and Guynn 1985). At this level,
allocation of resources in habitat and fawn production/recruitment is
maximized. All deer in the herd will develop to the potential of the
habitat’s nutritional ceiling. In areas of suboptimal habitats with inherently
lower carrying capacities, this level may be too low to provide
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