Black Bears
Black Bear Facts
Identification
The black bear (Ursus americanus) is the smallest and most widely distributed
of the North American bears.
Adults typically weigh 100 to 400
pounds (45 to 182 kg) and measure
from 4 to 6 feet (120 to 180 cm) long.
Some adult males attain weights of
over 600 pounds (270 kg). They are
massive and strongly built animals.
Black bears east of the Mississippi are
predominantly black, but in the Rocky
Mountains and westward various
shades of brown, cinnamon, and even
blond are common. The head is moderately
sized with a straight profile
and tapering nose. The ears are relatively
small, rounded, and erect. The
tail is short (3 to 6 inches [8 to 15 cm])
and inconspicuous. Each foot has five
curved claws about 1 inch (2.5 cm)
long that are non-retractable. Bears
walk with a shuffling gait, but can be
quite agile and quick when necessary.
For short distances, they can run up to
35 miles per hour (56 km/hr). They are
quite adept at climbing trees and are
good swimmers.
It is important to be able to distinguish
between black bears and grizzly/
brown bears (Ursus arctos). The grizzly/
brown bear is typically much
larger than the black bear, ranging
from 400 to 1,300 pounds (180 to 585
kg). Its guard hairs have whitish or
silvery tips, giving it a frosted or “grizzly”
appearance. Grizzly/brown bears
have a pronounced hump over the
shoulder; a shortened, often dished
face; relatively small ears; and long
claws (Fig. 2).
Range
Black bears historically ranged
throughout most of North America
except for the desert southwest and
the treeless barrens of northern
Canada. They still occupy much of
their original range with the exception
of the Great Plains, the midwestern
states, and parts of the eastern and
southern coastal states (Fig. 3). Black
bear and grizzly/brown bear distributions
overlap in the Rocky Mountains,
Western Canada, and Alaska.
Fig. 2. Characteristics of black bears and grizzly/brown bears.
Black bear
No prominent
shoulder hump
Straight muzzle
Short curved claws
Prominent shoulder hump
Massive head
Long claws
Chunky build
Adult male
250 pounds
Adult female
150 pounds
Adult male
450 pounds
Dishface (long
upturned muzzle)
Grizzly/Brown bear
Less robust build
Habitat
Black bears frequent heavily forested
areas, including large swamps and
mountainous regions. Mixed hardwood
forests interspersed with
streams and swamps are typical habitats.
Highest growth rates are achieved
in eastern deciduous forests where
there is an abundance and variety of
foods. Black bears depend on forests
for their seasonal and yearly requirements
of food, water, cover, and space.
Food Habits
Black bears are omnivorous, foraging
on a wide variety of plants and animals.
Their diet is typically determined
by the seasonal availability of
food. Typical foods include grasses,
berries, nuts, tubers, wood fiber,
insects, small mammals, eggs, carrion,
and garbage. Food shortages occur
occasionally in northern bear ranges
when summer and fall mast crops
(berries and nuts) fail. During such
years, bears become bolder and travel
more widely in their search for food.
Human encounters with bears are
more frequent during such years, as
are complaints of crop damage and
livestock losses.
Fig. 3. Range of the black bear in North America.
Adult female
250 pounds
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General Biology,
Reproduction, and
Behavior
Black bears typically are nocturnal,
although occasionally they are active
during the day. In the South, black
bears tend to be active year-round; but
in northern areas, black bears undergo
a period of semihibernation during
winter. Bears spend this period of dormancy
in dens, such as hollow logs,
windfalls, brush piles, caves, and holes
dug into the ground. Bears in northern
areas may remain in their dens for 5 to
7 months, foregoing food, water, and
elimination. Most cubs are born
between late December and early February,
while the female is still denning.
Black bears breed during the summer
months, usually in late June or early
July. Males travel extensively in search
of receptive females. Both sexes are
promiscuous. Fighting occurs between
rival males as well as between males
and unreceptive females. Dominant
females may suppress the breeding
activities of subordinate females. After
mating, the fertilized egg does not
implant immediately, but remains
unattached in the uterus until fall.
Females in good condition will usually
produce 2 or 3 cubs that weigh 7 to 12
ounces (198 to 340 g) at birth.
After giving birth, the sow may continue
her winter sleep while the cubs
are awake and nursing. Lactating
females do not come into estrus, so
females generally breed only every
other year. Parental care is solely the
female’s responsibility. Males will kill
and eat cubs if they have the opportunity.
Cubs are weaned in late summer
but usually remain close to the female
throughout their first year. This social
unit breaks up when the female comes
into her next estrus. After the breeding
season, the female and her yearlings
may travel together for a few weeks.
Black bears become sexually mature at
approximately 3 1/2 years of age, but
some females may not breed until their
fourth year or later.
In North America, black bear densities
range from 0.3 to 3.4 bears per square
mile (0.1 to 1.3 bears/km2). Densities
are highest in the Pacific Northwest
because of the high diversity of habitats
and long foraging season. The
home range of black bears is dependent
on the type and quality of the
habitat and the sex and age of the bear.
In mountainous regions, bears encounter
a variety of habitats by moving up
or down in elevation. Where the terrain
is flatter, bears typically range
more widely in search of food, water,
cover, and space. Most adult females
have well-defined home ranges that
vary from 6 to 19 square miles (15 to
50 km2). Ranges of adult males are
usually several times larger.
Black bears are powerful animals that
have few natural enemies. Despite
their strength and dominant position,
they are remarkably tolerant of
humans. Interactions between people
and black bears are usually benign.
When surprised or protecting cubs, a
black bear will threaten the intruder by
laying back its ears, uttering a series of
huffs, chopping its jaws, and stamping
its feet. This may be followed by a
charge, but in most instances it is only
a bluff, as the bear will advance only a
few yards (m) before stopping. There
are very few cases where a black bear
has charged and attacked a human.
Usually people are unaware that bears
are even in the vicinity. Most bears
will avoid people, except bears that
have learned to associate food with
people. Food conditioning occurs
most often at garbage dumps, campgrounds,
and sites where people
regularly feed bears. Habituated, foodconditioned
bears pose the greatest
threat to humans (Herrero 1985,
Kolenosky and trathearn 1987).
Damage and Damage
Identification
Damage caused by black bears is quite
diverse, ranging from trampling sweet
corn fields and tearing up turf to
destroying beehives and even (rarely)
killing humans. Black bears are noted
for nuisance problems such as scavenging
in garbage cans, breaking in
and demolishing the interiors of cabins,
and raiding camper’s campsites
and food caches. Bears also become a
nuisance when they forage in garbage
dumps and landfills.
Black bears are about the only animals,
besides skunks, that molest beehives.
Evidence of bear damage includes broken
and scattered combs and hives
showing claw and tooth marks. Hair,
tracks, scats, and other sign may be
found in the immediate area. A bear
will usually use the same path to
return every night until all of the
brood, comb, and honey are eaten.
Field crops such as corn and oats are
also damaged occasionally by hungry
black bears. Large, localized areas of
broken, smashed stalks show where
bears have fed in cornfields. Bears eat
the entire cob, whereas raccoons strip
the ears from the stalks and chew the
kernels from the ears. Black bears prefer
corn in the milk stage.
Bears can cause extensive damage to
trees, especially in second-growth forests,
by feeding on the inner bark or by
clawing off the bark to leave territorial
markings. Black bears damage
orchards by breaking down trees and
branches in their attempts to reach
fruit. They will often return to an
orchard nightly once feeding starts.
Due to the perennial nature of orchard
damage, losses can be economically
significant.
Few black bears learn to kill livestock,
but the behavior, once developed, usually
persists. The severity of black bear
predation makes solving the problem
very important to the individuals who
suffer the losses. If bears are suspect,
look for deep tooth marks (about 1/2
inch [1.3 cm] in diameter) on the neck
directly behind the ears. On large
animals, look for large claw marks
(1/2 inch [1.3 cm] between individual
marks) on the shoulders and sides.
Bear predation must be distinguished
from coyote or dog attacks. Coyotes
typically attack the throat region. Dogs
chase their prey, often slashing the
hind legs and mutilating the animal.
Tooth marks on the back of the neck
are not usually found on coyote and
dog kills. Claw marks are less prominent
on coyote or dog kills, if present
at all.
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Different types of livestock behave
differently when attacked by bears.
Sheep tend to bunch up when
approached. Often three or more will
be killed in a small area. Cattle have a
tendency to scatter when a bear
approaches. Kills usually consist of
single animals. Hogs can evade bears
in the open and are more often killed
when confined. Horses are rarely
killed by bears, but they do get clawed
on the sides.
After an animal is killed, black bears
will typically open the body cavity and
remove the internal organs. The liver
and other vital organs are eaten first,
followed by the hindquarters. Udders
of lactating females are also preferred.
When a bear makes a kill, it usually
returns to the site at dusk. Bears prefer
to feed alone. If an animal is killed in
the open, the bear may drag it into the
woods or brush and cover the remains
with leaves, grass, soil, and forest
debris. The bear will periodically
return to this cache site to feed on the
decomposing carcass.
Black bears occasionally threaten
human health and safety. Dr. Stephen
Herrero documented 500 injuries to
humans resulting from encounters
with black bears from 1960 to 1980
(Herrero 1985). Of these, 90% were
minor injuries (minor bites, scratches,
and bruises). Only 23 fatalities due to
black bear attacks were recorded from
1900 to 1980. These are remarkably
low numbers, considering the geographic
overlap of human and black
bear populations. Ninety percent of all
incidents were likely associated with
habituated, food-conditioned bears.
Legal Status
In the early 1900s, black bears were
classified as nuisance or pest species
because of agricultural depredations.
Times have changed and bear distributions
and populations have diminished
because of human activity. Many
states, such as Colorado, Idaho, Minnesota,
Montana, New Mexico, Oregon,
Utah, and Wisconsin, manage the
black bear as a big game animal. Most
other states either consider black bears
as not present or completely protect
the species. In most western states,
livestock owners and property owners
may legally kill bears that are killing
livestock, damaging property, or
threatening human safety. Several
states require a permit before removing
a bear when the damage situation
is not acute.
In states where complete protection is
required, the state wildlife agency or
USDA-APHIS-ADC will usually offer
prompt service when a problem
occurs. The problem bear will be livetrapped
and moved, killed, and/or
compensation for damage offered. In a
life-threatening situation, the bear can
be shot, but proof of jeopardy may be
required to avoid a citation for illegal
killing.
Damage Prevention and
Control Methods
Exclusion
Fencing has proven effective in deterring
bears from landfills, apiaries, cabins,
and other high-value properties.
Fencing, however, is a relatively
expensive abatement measure. Consider
the extent, duration, and expense
of damage when developing a prevention
program.
Numerous fence designs have been
used with varying degrees of success.
Electric fence chargers increase ffectiveness.
Depending on the amount of
bear pressure, use an electric polytape
portable fence (Fig. 4), or a weldedwire
permanent fence (Fig. 5).
Fence Energizing System and
Maintenance. To energize the fences,
use a 110-volt outlet or 12-volt deep
cell (marine) battery connected to a
high-output fence charger. Place the
fence charger and battery in a case or
empty beehive to protect them against
weather and theft. Drive a ground rod
5 to 7 feet (1.5 to 2.1 m) into the
ground, preferably into moist soil.
Connect the ground terminal of the
charger to the ground rod with a wire
and ground clamp. Connect the positive
fence terminal to the fence with a
short piece of fence wire. Use connectors
to ensure good contact. Electric
fences must deliver an effective shock
to repel bears. Bears can be lured into
licking or sniffing the wire by attaching
attractants (salmon or tuna tins and
bacon rinds) to the fence. Grounding
may be increased, especially in dry,
sandy soil, by laying grounded chicken
wire around the outside perimeter of
the electric fence.
Check the fence voltage each week at a
distance from the fence charger; it
should yield at least 3,000 volts. To
protect against voltage loss, keep the
battery and fence charger dry and
their connections free of corrosion.
Make certain all connections are secure
and check for faulty insulators (arcing
between wire and post). Also clip
vegetation beneath the fence. Each
month, check the fence tension and
replace baits with new salmon tins and
bacon rinds. Always recharge the batteries
during the day so that the fence
is energized at night.
Black bears are strong enough to tear
open doors, rip holes in siding, and
break glass windows to gain access to
food stored inside cabins, tents, and
other structures. Use solid frame construction,
3/4-inch (2-cm) plywood
sheeting, and strong, tight-fitting shutters
and doors. Steel plating is more
impervious than wood.
Bear-proof containers are available for
campers in a variety of sizes. They can
be used to safely store food and other
bear attractants during backpacking
trips or other outdoor excursions. In
the absence of bear-proof containers,
store food in airtight containers and
suspend them by rope between two
tall trees that are at least 100 yards (100
m) downwind of your campsite.
Food, supplies, and beehives can be
stored 15 to 20 feet (4 to 6 m) above
ground on elevated platforms or bear
poles. Support poles should be at least
6 inches (15 cm) in diameter and
wrapped with a 4-foot-wide (1.4-m)
piece of galvanized sheet metal, 6 to 7
feet (2 m) above ground. You can also
place one or two hives on a flat or lowsloping
garage roof. Be sure to add
extra roof braces because two hives
full of honey can weigh 800 pounds
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Gate handles
Guy wire
Ground rod
Beehive
Insulator
(360 kg) or more. An innovative technique
for beekeepers is to place hives
on a fenced (three-strand electric)
flatbed trailer (8 feet x 40 feet [2.4 m x
12.2 m]). Though expensive, this
method makes hives less vulnerable to
bear damage and makes moving them
very easy.
Cultural Methods
Prevention is the best method of controlling
black bear damage. Sanitation
and proper solid waste management
are key considerations. Store food,
organic wastes, and other bear attractants
in bear-proof containers. Use garbage
cans for nonfood items only.
Implement regular garbage pickup
and practice incineration. Reduce
access to landfills through fencing, and
bury refuse daily. Eliminate garbage
dumps.
Place livestock pens and beehives at
least 50 yards (50 m) away from
wooded areas and protective cover.
Confine livestock in buildings and
pens, especially during lambing or
calving seasons. Remove carcasses
from the site and dispose of them by
rendering or deep burial.
Plant susceptible crops (corn, oats,
fruit) away from areas of protective
cover. Pick and remove all fruit from
orchard trees.
Remove protective cover from a radius
of 50 yards (50 m) around occupied
buildings and residences. Locate
campgrounds, campsites, and hiking
trails in areas that are not frequented
by bears to minimize people/bear
encounters. Avoid seasonal feeding
and denning areas and frequently used
game trails. Where possible, clear hiking
trails to provide a minimum viewing
distance of 50 yards (50 m) down
the trail.
Repellents
Capsaicin or concentrated red pepper
spray has been tested and used effectively
on black bears. The spray range
on most products is less than 30 feet
(10 m), so capsaicin is only effective in
close encounters. Capsaicin spray may
become more popular where use of
firearms is limited.
Toxicants
None are registered.
Fumigants
None are registered.
Trapping
Culvert and Barrel Traps. Live
trapping black bears in culvert or barrel
traps is highly effective and convenient
(Fig. 6). Set one or two culvert
traps in the area where the bear is
causing a problem. Post warning signs
on and in the vicinity of the trap. Use
baits to lure the bear into the trap.
Successful baits include decaying fish,
beaver carcasses, livestock offal, fruit,
candy, molasses, and honey. When the
trap door falls, the bear is safely held
without a need for dangerous handling
or transfer. Bears can be immobilized,
released at another site, or
destroyed if necessary. Trapped bears
that are released should first be transported
at least 50 miles (80 km), preferably
across a substantial geographic
barrier such as a large river, swamp, or
mountain range, and released in a
remote area. Remote release mechanisms
are highly recommended. Occasionally,
food-conditioned bears will
repeat their offenses. A problem bear
should be released only once. If it
causes subsequent problems it should
be destroyed.
Foot Snares. The Aldrich-type foot
snare (Fig. 7) is used extensively by
USDA-APHIS-ADC and state wildlife
agency personnel to catch problem
bears. This method is safe, when correctly
used, and allows for the release
of nontarget animals. Bears captured
in this manner can be tranquilized,
released, translocated, or destroyed.
Use baits as described previously to
attract bears to foot snare sets.
The tools required for the pipe set are
an Aldrich foot snare complete with
the spring throw arm, a 9-inch (23-cm)
long, 5-inch (13-cm) diameter piece of stove pipe, iron pin, hammer, and
shovel. Cut a 1-inch (2.5-cm) slot,
6 1/2 inches (16.5 cm) long, down one
side of the pipe. Place the pipe in a
hole dug 9 inches (23 cm) deep into the
ground. Cut a groove in the ground to
accommodate the spring throw arm so
that the pan will extend through the
slot into the center of the pipe. The top
of the pipe should be level with the
ground surface. Anchor the pipe
securely to the ground, where possible,
by attaching it to spikes or a
stake driven into the ground inside the
can. Bears will try to pull the pipe out
of the ground if it “gives.” The spring
throw arm should be placed with the
pan extending into the pipe slot 6
inches (15 cm) down from the top of
the pipe. Pack soil around the pipe 1
inch (2.5 cm) from the top. Leave the
pipe slot open and the spring uncovered.
Loop the cable around the pipe,
leaving 1/2 inch (1.3 cm) of slack.
Place the cable over the hood on the
spring throw arm, then spike the cable
to the ground in back of the throw
arm. The cable is spiked to keep it
flush to the ground so that it will not
unkink or spring up prematurely.
Cover the cable loop with soil to the
top of the pipe. Anchor the cable
securely to a tree at least 8 inches (20
cm) in diameter. Cover the spring
throw arm and pipe slot with grass
and leaves. Place a few boughs and
some brush around the set to direct
the bear into the pipe. The slot in the
pipe and the spring throw arm should
be at the back of the set. The bear can
approach the set from either side or
the front. Melt bacon into the bottom
of the pipe and drop a small piece in.
The bacon should not lie on the pan.
Other bait or scent, such as a fishscented
rag, may be used. Place a 15-
to 20-pound (6.8- to 9-kg) rock over the
top of the pipe. Melt bacon grease on
the top of it or rub it on. The rock will
serve to prevent humans, birds, ontarget
wild animals, and livestock
from being caught in the snare. The
bear will approach the set and proceed
to lick the grease off the rock. It will
then roll the rock from the top of the
pipe and try to reach the bait with its
mouth. When this fails, it will use a
front foot, which will then be caught in
the snare.
The bear will try to reach the bait first
with its mouth and may spring the set
if the pan is not placed the required 6
inches (15 cm) below the top of the
pipe. Pipe sets are more efficient, more
economical, and safer than leghold
traps. Sources of bear foot snares are
found in Supplies and Materials.
*The above information was taken from a University of Nebraska Web site with
express permission of Stephen Vatassel, wildlife damage project coordinator.
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