in and Around Buildings
Chris Sansone and Michael Merchant*
oney bees are an important part of the
easy to distinguish bees
natural landscape and valuable to the Texas
from wasps. Bees are
Heconomy. The beekeeping industry in Texas generally hairy, with stout
generates an estimated $10.4 million annually. Agri-
bodies and wide, ? attened
cultural crops pollinated by bees have a value of $40
hind legs for carrying pol-
billion. Unfortunately, honey bees become unwel-
len (see ? gure). Wasps are
come guests when they nest around homes, schools
generally smooth or have
and businesses. The presence of the Africanized
scattered hairs; they also
honey bee in most Texas counties makes the risk of
have distinct “waists.”
encountering bees even greater. People should know
Another way to tell the
Bees can construct large
how to protect their homes and businesses from bee
two types of insects apart
wax nests rapidly once
they enter a home. For this
is to ? nd the nest or hive.
reason, both bees and nests
Honey bee colonies build
should be removed as soon
as possible. (Photo courtesy
a wax comb in which to
Bees vs. Wasps
rear their young and store
Honey bees are not the only stinging insects that
food. Social wasps form nests of paper-like material.
can set up residence in a building. Social wasps, such
The Mexican honey wasp or Mexican bee, Brachy-
as paper wasps, hornets and yellow jackets, also can
gastra melli? ca, is the only wasp that stores honey,
become pests in and around structures. It is usually
but its nest is made of a paper-like material and not
wax comb. The Mexican honey wasp is smaller than
a honey bee and very docile; there is usually no need
to remove its nest.
Wasp nests are often found under the eaves of
buildings or under porches, steps, benches or furni-
Social wasps are quick to sting when defending
their nests. Their attacks can be severe because they
cooperate to defend the nest and because individual
A honey bee (left) is distinguished from a yellowjacket wasp
wasps can sting repeatedly. Honey bees can sting
by its hairy body and wide rear legs designed for carrying
only once. Texas Cooperative Extension publication
pollen. (Photo courtesy of Michael Merchant.)
L-1828, Paper Wasps, Yellowjackets and Solitary
*Extension Entomologists, The Texas A&M University System.
Wasps, provides more information on wasps.
European bees introduced to Brazil and other
tropical areas either did not survive or did not produce
honey as successfully as in temperate climates. In an
effort to improve honey production, scientists in South
America crossed European bee races with African
bee races. Honey production did improve, but an un-
fortunate result of this cross was that the hybrid bees
exhibited the highly defensive behavior of the African
race. The Africanized bees inadvertently escaped from
a lab in South America in 1957, spread throughout
most of South and Central America, and entered the
United States through Texas in 1990.
Honey bee workers surround a queen bee. Bees are likely to
sting only when they perceive a threat to the nest and queen.
(Photo courtesy of USDA-ARS.)
Honey Bee Attacks
Africanized and European bees are so closely
related that it is almost impossible to tell them apart
except with genetic analysis or laboratory measure-
The honey bee, Apis mellifera Linnaeus, is a social
ments. However, their behavior is very different.
insect that lives in colonies. Each bee colony contains
Africanized bees are more sensitive to nest distur-
one fertile queen, drone bees and worker bees. The
bance. When disturbed (by activity near the colony,
queen is the only female that can lay fertilized eggs
vibrations from lawn equipment, etc.), established
and she can live 2 to 5 years. The drones are male
honey bee colonies may respond by attacking any-
bees. Their function is to mate with new queens.
thing within their territory. This is true for both
Drones cannot sting. The number of drones is highest
Africanized and European bees. However, Africanized
in the spring and summer. Most bees in a colony are
bees respond more quickly, send more bees from the
workers. Workers are infertile females. They perform
colony to drive the intruder away, and pursue intrud-
most of the functions bees are known for, such as
ers farther than European bees do.
making honey and defending the colony. There may
The venom of Africanized and European bees
be as many as 60,000 workers in a healthy, productive
is chemically identical, but Africanized bees are a
colony. The average number is 30,000.
greater threat because they are more likely to sting in
Honey bees occasionally move all or part of their
greater numbers. Children are more susceptible to the
colony to new nesting locations. This behavior is
venom than adults.
called “swarming,” and it is part of the colony’s nor-
Pets and livestock in con? ned areas are extremely
mal reproductive process. Swarms occur most often
vulnerable to bee attacks because they have no way
in the spring and early summer and usually start as
to escape. Pet and livestock owners should watch for
colonies become crowded. When a colony prepares
bees in the area and make sure animals can seek shel-
to swarm, the bees produce a new queen. The old
ter (e.g., a “doggy door” or other escape route).
queen and about half of the worker bees will leave the
If attacked by bees, you should cover your face
parent colony to establish a new colony, allowing a
and move out of the bees’ territory as fast as pos-
new queen to take over the remaining colony. When a
sible. European bees usually defend an area within
swarm selects a new nesting site, the bees begin build-
100 yards of the colony, while Africanized bees will
ing comb in which to store food and rear young. A new
defend an area within 400 yards of the colony. Taking
colony will become defensive within 2 to 4 weeks.
shelter in a car or house is often the best strategy, even
Honey bees are not native to the Americas. The
though a few bees may follow. Do not try to trick
Spanish introduced the ? rst honey bee colonies in the
the bees by hiding or playing dead because they will
early part of the 16th century. There are many races of
continue the attack as long as you are within their ter-
A. mellifera, and all have different physical character-
istics and behaviors. However, since all the races are
If you see someone else being attacked, do not
the same species, bees from one race can mate with
attempt to keep the bees off of the victim with a water
bees of another race.
foraging bees from gathering around a home or busi-
ness, remove or prevent access to attractants such as
ripening fruit, opened soda cans and pet water dishes.
Make sure outdoor garbage receptacles are covered
and well-sealed. Some ? owers, trees and shrubs at-
tract bees when in bloom. It is impractical to try to
remove all the plants that might attract bees, so people
with a fear of bees or allergies to bee venom should
simply avoid those areas when bees are foraging.
Swarming bees. Many people have never encoun-
An Africanized honey bee (left) and a European honey
tered bee swarms even though they occur every year.
bee. Despite size differences in these two individuals, the
two strains cannot be distinguished visually. (Photo
With literally thousands of bees in the air, swarms
courtesy of USDA-ARS.)
may appear dangerous. In fact, they pose little threat.
Eventually the swarm will land and remain clustered
Once away from
in one place for a few hours or several days. During
the attack, remove the
that time, scout bees are
stingers as soon as pos-
looking for a suitable nest-
sible. Stingers should
ing site. Once the scouts
be scraped out with a
? nd a new nest site and
? ngernail, knife or some
communicate its location
other sharp object. Sting-
An Africanized honey bee
to the swarm, the bees will
(left) and a European honey
ers continue to inject
move on to their new home.
bee on a honey comb.
venom for many minutes
Despite color differences
If a swarm lands in a
after the initial sting.
in these two individuals,
remote site, it should be
the two strains cannot be
The sooner a stinger is
left alone. The swarm does
distinguished visually. (Photo
removed, the less venom
courtesy of USDA-ARS.)
not contain stored food or
will be injected. If you
immature bees so the bees
experience hives, dif? culty breathing, or other signs
A honey bee swarm. (Photo
have nothing to defend and
courtesy of B. Pierson.)
of an allergic reaction, you should seek medical atten-
are unlikely to sting.
Swarms that land near buildings or high traf? c
areas should be managed. Bees may try to nest in wall
voids or ? oors of buildings if they can gain entry. Pro-
Managing Foraging Bees and Swarms
fessional and hobby beekeepers are often unwilling to
Honey bees are not truly aggressive—that is, bees
collect swarms because of the possibility of introduc-
do not search for someone or something to attack. But
ing diseases, mites or Africanized bees into their own
like social wasps, honey bees are highly defensive and
colonies. If no one can be found to remove a swarm
will attack anything that seems to threaten the colony.
near a building or in a high traf? c area, the swarm
You can lessen your risk of a bad experience with
may need to be destroyed.
bees by learning more about their behavior.
The presence of a swarm may also indicate that
Foraging bees. It is
a colony is nearby. Newly formed swarms tend to
common to see honey
gather near their former nesting site for a short while
bees foraging for food and
after emerging. You should scan the area carefully to
water around homes and
determine if there is a colony nearby that should be
other structures. Foraging
bees are away from the
Because swarms do not have a nest to defend and
colony and are not likely
the bees in the swarm are often full of honey, swarm-
to sting because they have
Bees are valuable pollinators
ing bees are usually more docile than established colo-
nothing to defend. Bees
and rarely sting when they
are away from the nest
nies and less likely to sting. However, there is always
visiting ? owers and other
searching for nectar.
a risk when working around bees. Therefore, Texas
food sources should be left (Photo courtesy of Michael
Cooperative Extension recommends that you contact a
undisturbed. To discourage
pest control professional to manage a swarm.
Managing Bees in Buildings
Although some pest control companies repair the
damage caused by nest removal, most prefer to rec-
The most important step is to prevent honey bees
ommend a good contractor for that work. It is very
from entering a building. Block all holes where pipes
important to seal all entrances tightly once the bees
and wiring enter, cracks in window framing, knot
are controlled so that bees won’t ? nd their way into
holes in wood siding, weep holes in bricks, and cracks
the building again.
where wood and brick join. Most of these holes can
Some pest control companies make the effort to re-
be ? lled with caulking, but holes necessary for air
move bees alive, although this is not always practical.
? ow should be blocked with wire screen. The screen
Removing bees alive is dif? cult, takes more time, and
mesh should be less than 1/8 inch. Chimneys should be
costs more. Most companies prefer to simply extermi-
properly capped. Removing a honey bee nest can eas-
nate the colony and remove the hive.
ily cost hundreds of dollars, so prevention is the best
Managed Bee Colonies
Honey bees that have moved into a structure
should be destroyed as quickly as possible. The longer
It is illegal for anyone other than an apiary inspec-
you delay, the more dif? cult the job is.
tor to kill any managed colony of honey bees without
the owner’s permission. If a managed colony needs
Hiring a Professional
to be moved, contact the owner. All apiaries must be
marked in some way that identi? es the owner. Contact
The job of collecting a swarm or managing a colo-
the state apiary inspection service (979-845-9714) for
ny in a building should be left to skilled, professional
assistance in identifying the owner of any problem
pest control companies. Professionals have the tools
and equipment to do a proper job. Texas Cooperative
For more information on bees, please visit
Extension of? ces, ? re departments and other govern-
ment of? ces generally do not engage in bee control or
collect bees to determine if the bees are Africanized.
However, your county Extension of? ce may be able
to give you a list of local professionals. Make sure
• If bees are in a building, don’t block the entry
the person or company you hire has a valid license
points. Bees trapped in a wall will search for or
through the Texas Structural Pest Control Board.
create an alternate exit and may emerge inside
Without this license, professionals cannot legally
charge for bee control.
• Don’t assume that spraying a liquid insecticide
Look for a company that is familiar with both
or dust into the bee entry point will solve the
extermination and the removal of bee nests. Failure
problem. A nest may be several yards from the
to remove a bee nest can result in big headaches later.
entrance, and insecticides applied at the entrance
The larger the nest, the more problems you may have
often fail to kill the colony. In addition, killing
with odors (from dead bees and fermenting honey),
the bees may make it harder for a professional
staining, and other pests such as ants, cockroaches,
to locate the nest for removal. It is best to leave
carpet beetles, wax moths and rodents. Traces of old
control to the experts.
comb are highly attractive to bees, and they will re-
• Never use fumigants or any ? ammable com-
infest the building unless the nest is removed.
pounds in structures. These seldom work well
Experienced pest control companies know how
against protected bee nests and can pose a ? re
to locate a nest and remove it with minimal damage
or explosion hazard.
to the structure. Large bee colonies may have to be
• Don’t try to use honey or wax removed from a
treated more than once before they are eliminated.
treated nest because they are often contaminated
Immature bees in the comb at the time of pesticide
with dust, insulation or insecticides and are
application may continue to emerge up to 10 days
unsuitable for human use.
Tips for Professionals
• Be prepared. Do not attempt to control bees or other
• Educate customers about the importance of bee nest
stinging insects without wearing proper protective
removal and remove the nest as part of your service.
gear. Beekeeping supply houses sell veils, gloves
Provide the name of a reliable contractor or handy-
and protective suits. Even if the gear is rarely used,
man who can repair any damage to sheetrock or
your safety is worth the investment.
• Make sure your technicians are comfortable around
• Try to locate the nest before opening walls or ? oors.
bees and on ladders. Do not assign a bee or wasp
Bee nests can be located with special equipment.
control job to anyone who has a fear of heights or
A stethoscope can be used to locate the hive by
bees or who has a history of allergic reactions to
sound. Newer motion-detecting equipment also
can be used to locate nests in walls and ? oors.
• Use a safety harness. A harness is essential if you
Sometimes bees can be located by the warmth
will be extracting hives from the top of a ladder.
their activities generates.
A harvest provides security and leverage for lifting
• Use a smoker to calm agitated bees. Smokers are
available from bee supply companies. Do not use
• Encourage customers to have backyard bee swarms
a smoker inside a building; smoke odor can persist
collected or exterminated. Bee swarms, while not
indoors for weeks.
as aggressive as bees in a nest, can be even more
• Pyrethrins can be used for immediate nest removal,
expensive to control should they take up residence
but be sure to apply a residual insecticide to the
in the home. Liquid dishwashing detergent mixed
nest area after the comb is removed to prevent bees
with water can be sprayed through a B&G sprayer
from rebuilding. Resmethrin (or another labeled
to kill exposed bees (Note: Do not try this on bees
pyrethroid) has worked better if you will be treating
that have moved into a building). Soapy water is less
the nest ? rst and returning later to remove it.
likely to agitate bees than other methods. A mixture
• Remove as much of the hive, honey and dead bees
of 1 cup of liquid soap or detergent in a gallon of
from the nest location as possible. Masses of dead
water will immediately disable bees that are wetted
bees and nest debris can cause infestations of cock-
with the solution. Wetted bees die quickly. Continue
roaches, ants and carpet beetles.
to spray the swarm as the outer layer of bees falls
• Have your technician, the homeowner or a contrac-
to the ground. All bees must be thoroughly covered
tor seal the nest entrance and other potential nest
with the soapy water to ensure that the swarm is
entrances after you leave. Bees frequently reinfest
eliminated. Catch dying bees in a garbage bag or
old nest sites.
trash can as the bees are sprayed with the soapy
The information given herein is for educational purposes only. Reference to commercial products or trade names is made
with the understanding that no discrimination is intended and no endorsement by Texas Cooperative Extension is implied.
Produced by Agricultural Communications, The Texas A&M University System
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Issued in furtherance of Cooperative Extension Work in Agriculture and Home Economics, Acts of Congress of May 8, 1914, as amended, and June
30, 1914, in cooperation with the United States Department of Agriculture. Edward G. Smith, Interim Director, Texas Cooperative Extension, The Texas
A&M University System.