Dealing
with Unwanted Wildlife in an Urban Environment1
Background
Because of its great diversity of
habitat types, Florida is home to more wildlife species than most
other states. It is literally impossible to live in this state
without seeing or hearing wildlife on a daily basis. Many of these
experiences are enjoyable; others are confrontational. Unpleasant
encounters with our wild neighbors can result in human death,
injury, or fear of injury, property damage, or minor nuisances. Some
of our frustrations with wildlife can be alleviated by simply
learning why a situation occurs. Others require more action-oriented
prevention and control techniques.
Understanding
Wildlife: Myth v. Facts
Understanding is the key to wildlife
problem solving. Knowing why the snake is in your garden, the
armadillo is digging up your lawn, or the woodpecker is drilling
holes in the side of your house is an essential first step toward
resolving these and other wildlife nuisance problems. Often times
the reasons are obvious. Snakes prefer shaded areas where they might
find a toad, mouse, or other food item. Armadillos don't excavate
lawns as a prank. They are merely looking for ants, grubs, and other
soil-dwelling insects. Some problems such as woodpeckers damaging
house siding may be puzzling and require some research. Pecking in
one spot that produces a loud resonating sound is a method used to
mark territories. Other types of pecking patterns may be the result
of woodpeckers foraging for wood-boring insects that have infested
your siding. Sometimes the opinion of a wildlife expert is needed to
help interpret your findings.
Misunderstandings are common causes of
many frustrations and fears that people have about wildlife. For
example, contrary to popular belief, most snakes in Florida couldn't
even hurt you let alone kill you. All bats don't carry rabies.
Separating myths from facts can alleviate many of these phobias and
help you to appreciate wildlife more for their beneficial values,
particularly in our urban environments.
Solutions
to Some Common Wildlife Problems
Snakes
Problems: Many people have a
strong anxiety toward all snakes (ophidiophobia). The bites
of a few non-venomous snakes can cause noticeable injuries (Figure 1). Venomous snake bites can be lethal (Figure 2). To most people, snakes are unwanted
visitors on our properties and in our homes.
Understanding the Problems: People are not born
with an innate fear of snakes. It is merely one of those things we
were taught at an early age much like our attitudes toward touching
the kitchen range or going into the street. As we grew older we
learned that ranges and streets weren't the terrible things that we
once thought, but they should be respected. However, our fear of
snakes was continually reinforced and many people have never learned
that there is no logical reason to have an extreme dread of all
snakes. Statistics show that the potential danger of highway
accidents is at least a hundred times greater than the chance of
being bitten by a venomous snake. There are over 100,000 cases of
dog bite reported in Florida each year compared to only an estimated
200 people bitten by venomous snakes. Snake bite related deaths have
occurred at a rate of about one every four or five years in Florida.
Mortality figures for lightning strikes and bee stings are much
greater. Snakes are not aggressive and will not charge or chase
after people. Their typical reaction to a human intruder is to crawl
away and hide; however, snakes may react differently if they feel
threatened. Some will hiss, shake their tail, and even try to bite
an intimidating object. All snakes stick out their tongue frequently
to smell their environment much the same way a dog sniffs at
things.
Prevention and Control Methods: There are no
repellents, toxicants, or fumigants registered for snakes. Many home
remedies such as blood, hair, and various chemicals may seem to work
in some situations. However, unless the item has been scientifically
tested, its effectiveness is questionable. The frequency of snake
visits to your yard and home can be reduced by eliminating firewood
stacks, debris, boards and other objects lying close to the ground
creating preferred cool, damp, and dark shelter or prey habitat
areas.
Snakes can be removed from inside
buildings by placing glueboards (see Figure 3) or funneled minnow
traps (see Figure 4) in snake-traveled areas such as along
walls.
Glueboards have been tested and proven
successful at holding even 6 foot diamondback rattlesnakes.
Glueboards are sold at hardware stores to control rodents and minnow
traps are sold at bait and tackle shops. They should be nailed to a
larger board so the whole assembly can be handled at a safe distance
from a stuck snake. Once outside, pouring cooking oil on the glue
board will allow the snake to free itself. A snake caught in a
minnow trap can be prudently dealt with by scooping the trap up with
a beach towel or blanket. These traps can be easily opened to
release the snake. A broom also can be used to sweep a snake into a
trash can for removal outside.
Armadillos
Problems: The most notable
armadillo damage occurs as a result of their rooting in lawns,
vegetable gardens, and flower beds (seeFigure 5). Armadillos live in dens and some damage
also can be caused by their burrowing under foundations, driveways,
and other structures.
Understanding the Problems: More than 90 percent of
the armadillo's diet is made up of insects and their larvae that
live in the soil. They also feed on earthworms, scorpions, spiders,
and other invertebrates. Armadillos (Figure 6) are most active at night, when they make
small cone-shaped holes in the ground while rooting for food.
Prevention and Control Methods: There are no successful
repellents, toxicants, or fumigants registered for armadillos. The
use of insecticides to reduce food sources also has not been proven
to stop armadillo digging. A fence slanted outward at a 40° angle,
with a portion buried may be a somewhat effective barrier under
certain conditions. Although live-trapping armadillos is very
difficult, some people have experienced limited success by using a
10x12x32in (25x30x80cm) live or box trap. The bait used by
successful trappers is earthworms in a ball of dirt and placed in
the toe of an old nylon stocking. Trapping is most effective when
leaf litter or soil is placed over the trap entrance. Current
Florida law (Florida Fish and Wildlife Conservation Commission Rule
68A-9.010) requires that all animals captured as a "nuisance" either
be humanely destroyed or released on the same contiguous property as
they are captured to prevent ecological problems or spreading of
diseases. Shooting is another effective method to eliminate nuisance
armadillos. However, discharging firearms is illegal in some areas
and it also is illegal to use artificial lights other than outdoor
house lights to aid in shooting at night. Armadillo meat is edible
if properly prepared.
Bats
Problems: Bats may enter
buildings and become a nuisance by their squeaking, scratching,
scrambling, and crawling in attics, walls, and chimneys. Bat
droppings can accumulate and cause quite a stench in buildings and
an unsightly mess on the outside of buildings. Rabies is a potential
health hazard with bats.
Understanding the Problems: Bats are active at
night and seek dark and secluded roosting areas during the day.
Their natural roosting habitat is caves and trees.
Most bats are able to squeeze
through slits and cracks no wider than 3/8 inch. Bats commonly enter
a house through the overhang of the roof or eaves. Inside they are
most often found in attics, between roofs and ceilings, in crevices
around the roof, in walls, in chimneys, and occasionally in crawl
spaces. Outside they may roost behind shutters or under wood
shingles, roofing, drain gutters, awnings, overhang trim, and
flashing around chimneys. Bats also fly around swimming pools to
drink and to catch insects. Street and porch lights may attract
flying insects which, in turn, attract bats. The incidence of rabies
in bats has been greatly exaggerated. During the past 30 years, only
eight human fatalities in the United States and Canada have been
attributed to rabid bats. More people die annually from dog attacks,
bee stings, lightning, and household accidents than from
bat-transmitted rabies.
Prevention and Control Methods: Excluding bats from
buildings is the only legal solution (see Figure 8). Exclusion methods can be applied only
from August 15 through April 15, outside of the maternity season.
During the summer it is not legal to exclude or trap bats because of
the high likelihood of dependent baby bats being left inside the
structure. Bats should be out of the building before bat proofing
begins so as not to seal bats inside. Holes should be blocked after
dark in the early evening when the bats have left the structure to
feed. Several successful bat excluders with one-way valve doors and
funnel screens have been developed. Repellents such naphthalene
crystals, illumination, and high frequency sounds have provided
temporary relief in some situations. Roosting boxes (seeFigure 9) may attract bats that are excluded from
a building, but this is not recommended as a reliable bat control
method.
Woodpeckers
Problems: Woodpeckers (Figure 10) can peck holes in wooden house siding,
gutters, drainpipes, and chimney and exhaust vents. The noise and
damage from this pecking activity sometimes is annoying.
Understanding the Problems: There are three reasons
why woodpeckers peck on houses. The first and most common is to
establish territories and attract mates. This predominantly
springtime behavior, called drumming, generally is done in rapid
succession on resonant dead tree trunks or limbs. However, buildings
and utility poles, when available, are often alternatives. Drumming
may occur a number of times during a single day, and may last for
some days or months.
The second reason woodpeckers attack
our houses is to feed on insects that may have infested our siding
(Figure 11). They naturally search vertical
surfaces of tree trunks and branches for woodboring beetles,
carpenter ants, and other insects. The pecking style used for
feeding is much different than drumming. Only a few pecks are made
and then the resulting hole is explored with the bird's bill and
tongue. This behavior will continue until an insect is found or the
bird is satisfied that one is not there. Then the woodpecker may hop
a few inches away and peck at another place. The damage from this
feeding activity usually occurs in horizontal lines that follow
tunnels made by the insects.
The third reason for woodpecker damage
occurs when they excavate nesting cavities through house siding
(see Figure 12). Cedar siding is fairly soft and
particularly vulnerable to woodpecker attacks of this nature.
Fortunately, this attack is not very common.
Prevention and Control Methods: One of the most
effective methods of excluding woodpeckers from damaging wood siding
is to cover the siding with lightweight mesh nylon or plastic
netting hung from the eaves. The netting should be kept at least 3in
out from the siding. Another exclusion technique is to cover the
siding with sheets of plastic. Woodpeckers will not be able to perch
on this smooth surface. Limited success can be obtained in some
situations by using model owl or hawk silhouettes or various
noise-making devices. Woodpeckers can be very persistent and are not
easily driven from their territories or selected pecking sites. For
this reason, visual or sound types of repellents should be employed
as soon as the problem is identified and before territories are well
established.
Raccoons,
Skunks, and Opossums
Problems: These animals quite
often make pests of themselves by getting into garbage cans, eating
pet food, getting into attics or beneath houses, and eating
home-grown fruits and vegetables. Raccoons are a major carrier of
rabies in Florida.
Understanding the Problems: These three mammals are
opportunistic and have adapted well to urbanization (see Figure 13). They will eat any plant, insect, or
other animal food that is readily available. Raccoons have learned
that uncapped chimneys make very adequate substitutes for more
traditional hollow den trees.
Prevention and Control Methods: Garbage can raids may
be prevented by using metal or tough plastic containers with
tight-fitting lids. If lids do not fit tightly, it may be necessary
to wire, weight, or clamp them down. The containers also should be
tied to a support or held on a rack to prevent raccoons from tipping
them over. These animals will not be as attracted to your property
if you do not leave pet food outside at night. Access to chimneys
can be prevented by fastening a commercial cap of sheet metal and
hardware cloth over the top of the chimney. These animals can be
kept out from underneath houses by sealing off all possible
entrances. A good method to determine if the animal is out of the
sheltered area is to sprinkle a liberal amount of baking flour near
the entrance. Wait until an hour or so after dusk and see if there
are any tracks (see Figure 14) leading out of the entrance. If there
are, then seal it off. In certain cases, the construction of an
electric fence 6in off the ground will solve the problem. Repellents
such as naphthalene crystals and noise-making devices may have
limited temporary effectiveness.
Live traps baited with sardines or cat
food are effective for garden damage situations (see Figure 15). Once an animal is caught, another
problem is created--what to do with it. Trap and release of wildlife
is seldom biologically sound. Areas that appear suitable for release
probably are not. Areas without a resident population of the same
species as the relocated animal most likely do not meet its habitat
requirements. Relocation to already occupied areas causes problems
for both the relocated animal and the resident population of the
same species. Current Florida law (Florida Fish and Wildlife
Conservation Commission Rule 68A-9.010) requires that all animals
captured as a "nuisance" either be humanely destroyed or released on
the same contiguous property as they are captured to prevent
ecological problems or spreading of diseases. Animals can be
transported only for the purpose of traveling to a place where
euthanization procedures will be performed.
State
Laws and Rules Related to Wildlife Control Methods
The Florida Constitution has designated
the Fish and Wildlife
Conservation Commission (FWCC) as the legal steward of the
native wildlife resources of the state. The mission of this state
agency is to manage freshwater aquatic life and wild animal life and
their habitats to perpetuate a diversity of species with densities
and distributions that provide sustained ecological, recreational,
scientific, educational, aesthetic, and economic benefits.
There are certain laws, rules, and
regulations with which anyone who is baiting, trapping,
transporting, or killing nuisance wildlife should be aware. The
following laws have been paraphrased for the sake of brevity.
Laws
Florida
Statutes 372.662 to 372.667 deal with alligators.
It is unlawful to feed or entice wild alligators (Figure 16), or to harvest or sell them without the
required permits.
Florida
Statutes 372.86
to 372.92 prohibit
the possession or exhibition of poisonous or venomous reptiles (Figure 17) without first having obtained a special
permit, posting a bond, and complying with the safe housing and
transportation regulations.
Florida
Statute 372.922 and Rules adopted by
the FWC (see Rule 68A-4.001 below) state that it is unlawful to
possess certain native or non-indigenous wildlife for pets or
otherwise until the appropriate permit is obtained from the
Commission. There also is a Rule (see 68A-6 below) that allows many
non-native species to be kept without a permit.
Rules
Chapter 68A-4.001, Florida
Administrative Code (F.A.C.) is the Commission's
general prohibition on taking of wildlife. It states "no wildlife or
freshwater fish or their nests, eggs, young, homes or dens shall be
taken, transported, stored, served, bought, sold, or possessed in
any manner or quantity at any time except as specifically permitted
by these rules nor shall anyone take, poison, store, buy, sell,
possess or wantonly or willfully waste the same except as
specifically permitted by these rules."
Chapter 68A-6, F.A.C. prohibits the
possession of all wildlife for exhibition, public sale, or personal
use unless appropriate permits are obtained from the Commission.
This Rule also states pen specifications, and caging and
transportation requirements. No permit is required to possess the
following wildlife for personal use unless possession of a species
is regulated by other Rules of the Commission (e.g. venomous snakes
and endangered species): reptiles, gerbils, amphibians, shell
parakeets, rats and mice, canaries, moles, shrews, rabbits, hares,
squirrels, chipmunks, ferrets (European), lovebirds, guinea pigs,
cockatiels, hamsters, parrots, finches, mynah birds, toucans.
Chapter 68A-9.010, F.A.C. allows the killing of
destructive mammals except deer or black bear on your property by
means other than gun and light, steel traps or poison, provided that
the destructive mammals are killed only within the immediate
locality where damage is occurring. Birds other than blackbirds,
cowbirds, grackles, and crows may be killed only under authority of
a special permit issued by the U.S. Fish and Wildlife Service.
Chapter 68A-24.002, F.A.C. allows the taking of
opossums (Figure 18) and raccoons with a gun (.22 cal rifle
or .410 shotgun) and light at night throughout the year.
Chapter 68A-24.005, F.A.C. states that no person
shall transport within, into, or from the state any wild-trapped,
live raccoon.
Chapter 68A-25.003, F.A.C. explains that only
designated agent-trappers of the Commission are authorized to take,
possess, and kill those nuisance alligators specifically designated
by the Commission.
