BIOLOGICAL DATA AND HABITAT REQUIREMENTS
WILDLIFE SPECIES: Ursus americanus | Black Bear 



TIMING OF MAJOR LIFE HISTORY EVENTS : 
Breeding Season - May and June; mate about every 2 years
Gestation - delayed implantation of 6 to 7 months, until October or
            November
Birthing Season - Late November through February; one to three cubs average;
                  cubs remain with mother 1 or 2 years
Age of Maturity - 5 to 7 years, can mature in 3 years
Life Span - may exceed 30 years, but 10 years in the wild is average
Hibernation - 4 to 7 months between October and May; lasts longer in 
              cold climates
[7,11,17,25,39]


PREFERRED HABITAT : 
Black bears prefer forested and shrubby areas but use wet meadows, high
tidelands, ridgetops, burned areas, riparian areas, and avalanche chutes
[39].  They also frequent swampy hardwood and conifer forests [32].
Black bears prefer mesic over dry sites and timbered over open areas
[43].  After emerging from their winter dens in spring, they seek
southerly slopes at lower elevations for forage and move to northerly
and easterly slopes at higher elevations as summer progresses
[2,21,23,25,37,43,46].


COVER REQUIREMENTS : 
Black bears use dense cover for hiding and thermal protection, as well
as for bedding [25].  They climb trees to escape danger and use forested
areas as travel corriders.  Black bears hibernate during winter and may
build dens in tree cavities, under logs, rocks, in banks, caves, or
culverts, and in shallow depressions [17,38,44,46].


FOOD HABITS : 
Black bears eat a wide variey of foods, relying most heavily on grasses,
herbs, fruits, and mast [25].  They also feed on carrion and insects
such as carpenter ants (Campanotus spp.), yellow jackets (Vespula spp.),
bees (Apidae), and termites (Isoptera) [4,14].  Black bears sometimes
kill and eat small rodents and ungulate fawns.  Some common plant foods
are listed below: oak (Quercus spp.) and hazel (Corylus spp.) mast,
mountain ash (Sorbus spp.), tree cambium, dogwood (Cornus spp.),
manzanita and kinnikinnick (Arctostaphylos spp.), cranberry (Vibernum
spp.), blueberry and huckleberry (Vaccinium spp.), raspberry and
blackberry (Rubus spp.), rose hips (Rosa spp.), gooseberry (Ribes spp.),
sarsaparilla (Aralia nudicaulis), rhubarb (Polygonum alaskanum), lupine
(Lupinus spp.), northern bedstraw (Galium boreale), lousewort
(Pedicularis spp.), Labrador tea (Ledum groenlandicus), California
coffeeberry (Rhamnus californicus), squawroot (Conopholis americana),
dandelion (Taraxacum officinale), clover (Trifolium spp.), thistle
(Cirsium spp.), buffaloberry (Shepherdia canadensis), lomatium (Lomatium
spp.), cowparsnip (Heracleum lanatum), and pine nuts
[4,21,24,25,26,27,28,37,39,41,46].  Black bears also eat salmon
(Oncorynchus spp.) and raid orchards, beehives, and crop fields
[9,27,39].  They pick from garbage dumps and trash bins of private
homes.  Black bears may occasionally prey on domestic sheep and pigs
when their natual foods are scarce [26].


PREDATORS : 
Black bear predators include man, grizzly bears (Ursus arctos), and other
black bears.  Coyotes (Canis latrans) may prey on cubs [25].


MANAGEMENT CONSIDERATIONS : 
Black bears are as much an important game species as they are the center
of controversy across the continent.  Because their behavior has been
little understood, black bears have been feared and hated [25].  They
have also been portrayed as harmless play toys by film and television.
Their low reproductive rate and late sexual maturation make them
vulnerable to overharvest [13].  Their active foraging habits and
habitat encroachment by man have created man-bear conflicts
[9,32,34,41].

Logging can have both positive and negative effects on black bear
populations.  Many studies show that black bears will use clearcuts
older than 10 years, but in some areas cuts are not used for 20 years
[24,31,45,46].  Black bears will use cutover areas if fruit-producing
shrubs are present and hiding cover is available.  A study in northern
Idaho revealed that selection-cuts were the most important habitat
component for black bears because these units provided more food and
cover compared to clearcuts or mature stands [45,46].  Intensive
scarification of clearcuts can kill important food plants or eliminate
them for long time periods [33,45,46].  Many authors list management
strategies for timber harvesting in bear habitat [36,41,43,45,46].
Hannah [18] listed management techniques for enhancing oak stands to
create valuable mast crops.


REFERENCES : 
NO-ENTRY

Related categories for Wildlife Species: Ursus americanus | Black Bear