Abstract:
Management of deer populations is directed toward multiple
objectives. Deer populations on public and private lands belong to the
public and thus management is a political process. Four components
for an effective management system for deer populations are identified.
These are the set of objectives relating to the resource, the set of
regulations which will achieve the objectives, knowledge of the
expected population response to alternative management strategies,
and a means of monitoring these responses to determine whether or
not the objectives are being achieved.
Deer provide benefits mainly through the associated recreational
opportunities and cause costs by interacting with land based economic
activities such as agricultural crop production and reforestation. At
certain times of the year deer may also compete with domestic
livestock for forage. Deer also cause significant costs through collisions
with automobiles on the highways.
The extent of these benefits and costs, and others, is related to
the biosystem through parameters such as the size and composition of
the population, the extent of the hunting kill, and so on. In this thesis
a computer simulation model of the Mendocino County, California,
deer population is presented. The population is modeled as a density
dependent birth and death process. Hunting strategies are potentially
the most flexible management tool. Thus the model is structured to
permit detailed examination of the response over time of the population
to alternative hunting strategies.
In California, a bucks-only hunting strategy has been followed
since about the turn of the century. This study demonstrates that the
bucks-only strategy neither effectively controls the size of the deer
population, nor does it provide for the greatest recreational opportunities.
The extent of the costs referred to above are directly related
to the size of the population and the consumptive recreational benefits,
that is those due to hunting, are directly related to the size of the
hunting kill. Experiments with the model show that population control
can be achieved and the hunting kill can be increased by a mixed buck
and antlerless deer hunting strategy. Other results show that the
computer simulation model can provide information about the biosystem
which is not otherwise available.
Simulation methods permit considerable insights into the operation
and control of complex biosystems where the status of the systems
is time dependent and the systems are influenced by uncontrollable
elements so that at best the outcomes resulting from particular
management actions are uncertain. The simulation model used in this
study is applicable to other deer populations and other wildlife species.
