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 Not too many years ago,
white-tailed deer were present in just a few areas of
Mississippi. But times have changed. As a result of one
of the most successful restocking efforts in history,
white-tailed deer are abundant in every county in
Mississippi today. In fact, their abundance is becoming
problematic in many areas. Complaints arise from deer
depredation on gardens, shrubbery, and agricultural
crops. Their abundance is even dangerous, as
deer-vehicle collisions are on the rise.
So why
are deer causing problems? Many of the problems arising
from deer are actually due to the increasing human
population. In many areas deer are exceeding human
tolerance levels because of a lack of management. As
cities expand, suburban and urban areas are encroaching
into deer habitat. Many of these areas have little or no
deer management because of real or perceived safety
concerns, conflicting social attitudes and perceptions
about wildlife, hunting and firearm-discharge
restrictions, and liability or public relations
concerns.
The main complaints people have
concerning deer in urban and suburban areas are browsing
damage and deer-vehicle collisions. Many new plants are
placed around houses, and deer find these plants quite
appealing. This appeal results in browsing damage to
expensive landscape plants. Many people feed deer, which
further intensifies the problem. Deer that are fed
around houses become accustomed to people and their
automobiles. Deer-vehicle collisions are both expensive
and dangerous. In 1995, a study estimated that vehicle
repair costs from deer-vehicle collisions exceeded $1.1
billion annually. The study also estimated that 29,000
human injuries and 211 deaths occur annually from
deer-vehicle collisions.
Management options for
urban and suburban deer include lethal and non-lethal
methods. The lethal methods include hunting,
sharpshooting, and trapping and euthanasia. Hunting is
the most common method of managing deer herds in both
suburban and urban areas of Mississippi. Mississippi has
a four-month deer season, extending from October 1 until
January 31. Many urban and suburban areas do not allow
the discharge of firearms, but most do allow hunting
with archery equipment. A hunter may hunt with archery
equipment the entire four-month season. Hunting allows
for both recreational and consumptive management of the
deer herd. Hunting also results in no expense for the
community.
 Although not very common in
Mississippi, sharpshooting is another lethal management
technique employed by many states. Communities employ
trained, experienced personnel to lethally remove deer
through sharpshooting. The cost ranges from $91 to $310
per deer.
Trapping and euthanasia is another
lethal method used by several states to manage suburban
and urban deer. Deer are captured with box traps, Clover
traps, drop nets, or rocket nets and then euthanized.
This method has proven inefficient and expensive, with
costs exceeding $300 per deer.
Non-lethal
management techniques for suburban and urban deer are
preferred by the public in some states. Non-lethal
techniques include banning the feeding of deer in the
community, planting unpalatable landscape plants, use of
repellents, and fencing. A ban on deer feeding is only
effective when the community is fully supportive. The
presence of less palatable landscape plants can minimize
deer browsing but does not eliminate deer problems.
Repellents have been used to decrease deer browsing, but
they do not eliminate browsing pressure. Cost,
restrictions on use, and variable effectiveness are
limitations of repellents. Fencing can be used to limit
deer access to problem areas of larger size. Cost and
visual appearance are limitations of constructing
fences. Although these types of non-lethal management
techniques can decrease deer damage, they do not
decrease the number of deer present. Research is being
conducted to investigate the use of fertility control in
suburban and urban deer management to prevent the
increase of deer populations. Fertility control is
non-lethal and targets female reproduction. Fertility
control will not decrease the present deer population
but provides a means to prevent an increase in the
population. Four methods of fertility control being
researched are surgical sterilization, steroid
contraception, immunocontraception, and contragestation.
Surgical sterilization is a procedure in which the
ovaries are removed from does. The removal of ovaries is
called an ovariectomy. By removing the ovaries, the main
source of female reproductive hormones (estrogen and
progesterone) is eliminated and reproduction can not
take place. Fertility control by this method is
permanent. In addition to the expense of this method,
there are several other disadvantages. Does must be
captured and held for an extended period. The services
of a licensed veterinarian are required for the
ovariectomy. Capturing deer can result in injury, or
even death. Alterations in doe behavior may also occur
after the procedure.
Steroid contraception is a
form of fertility control that uses synthetic hormones
(progestins and estrogens) to prevent ovulation.
Implants containing synthetic hormones have been
effective in some studies, but steroids delivered orally
have shown limited success. The use of steroid
contraception has not been approved for use on free
ranging deer because of unknown long-term effects on
treated deer and consumption of treated deer by humans
and other animals.
Immunocontraception is the
administration of antifertility agents that prevent
conception by antibody production against proteins and
hormones essential for conception. Porcine Zona
Pellucida and Gonadotropin-releasing Hormone are two
agents that have been used to successfully control
reproduction in individual does. Administration of these
agents can be done using darts or biobullets (cellulose
biodegradable bullets, propelled by compressed air, used
to remotely deliver contraceptives). To maintain
infertility, booster shots must be administered. The use
of immunocontraception has not been approved for use in
free-ranging deer at this time.
Contragestation
may have the most negative perception of the four
methods of fertility control because it induces
abortions in does. Aborted fawn-like fetuses in areas
where observation by humans is likely, is not acceptable
for most communities. This method involves administering
a hormone (prostaglandin F2·) that regresses the corpus
luteum on the ovary of a pregnant doe. Once the corpus
luteum regresses, pregnancy cannot be maintained and the
fetus is lost. Administration of prostaglandin F2· is
normally done using a biobullet. This method of
fertility control has been proven to be safe and highly
effective. Risks from consuming does treated with
prostaglandin F2· are minimal because the hormone is
readily metabolized in the treated animal.
Complaints of deer damage in suburban and urban
areas are occurring in many areas across Mississippi. As
suburban and urban areas expand and deer populations
increase, more conflicts between humans and deer will
arise. Many management options exist for these areas,
but most are expensive and inefficient. While hunting
may not be applicable in all areas, it is the most
efficient and cost effective means of managing suburban
and urban deer populations.
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