|  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. WI
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