ABBA would like to thank the Black Bear Conservation Committee of Baton Rouge, Louisiana
for providing the following information:

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Reproduction
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Habitat Requirements
 
Black Bear Facts

According to Alabama Wildlife Federation's definitive reference book, Managing Wildlife (1998), black bears in Alabama are considered to be subspecies Ursus americanus floridanus, or the Florida black bear.  Historical status and distribution data are lacking for bears in Alabama; however, there are reports indicating "bears once occupied most forested areas in the Southeast" and reached their peak abundance in the early 1800s.  Since then, the decline in black bear abundance can be attributed to human disturbance, illegal kills, and habitat loss.  Combined with the naturally low reproductive rate of black bears, these are serious concerns for maintaining a health bear population.  In nearby Louisiana, Mississippi, and Texas, the Louisiana black bear is Federally listed as threatened under the Endangered Species Act.  During the listing process, U.S. Fish and Wildlife Service determined the status of the Florida black bear as "warranted but precluded" due to lack of data.  

Bears are one of the world's most adaptable carnivores. Their reasoning ability, long-term memory, omnivorous food habits, dexterity, speed, strength, sense of smell, and elusive behavior contribute to their success through evolutionary time.

Black bears in the Eastern U.S. are black with a brown muzzle, some with a distinct white "blaze" on their chest. Adult males generally weigh from 150 to 350 pounds, and adult females range from 120 to over 250 pounds. Body length of adults, nose to tail, ranges up to 6 feet.

Female black bears become sexually mature at 3 to 5 years of age and have 1 to 5 cubs every other year. The young remain with their mother the first year, den with her the following winter, and search for their own territory in their second summer.

Bears tend to range over large areas in search of basic needs such as food, escape cover, den sites, and mates. Males range over 40,000 acres while females usually maintain home ranges up 18,000 acres.

Although classified as carnivores, black bears are not active predators. They are opportunistic feeders and will eat almost anything that is available. Natural foods, such as berries and acorns, comprise a majority of a bear's diet, but bears readily take advantage of food options provided by agricultural crops such as corn, wheat, oats, and sugarcane, occasionally damage beehives in search of honey, and will readily become habituated to human garbage when the opportunity exists.

Black bears are very intelligent, shy and secretive animals, and generally work hard at avoiding contact with humans. Dangerous situations may occur whenever close human activity is perceived as threatening to the bear or its cubs. The best advice is for humans to avoid close bear encounters.

 
Physical Description

Black bears in the region are normally black with a brown muzzle and an occasional white blaze on the chest. Average body weights are 150 to 350 pounds for adult males and 120 to 250 for adult females.  Body lengths range from 3 to 6 feet from nose to their short tail. Size typically varies depending on the quality and quantity of available food.

 
Reproduction

Mating generally occurs in the summer months and egg implantation is usually delayed for about five months. Female black bears typically begin having cubs at three to five years of age. Females as young as two years of age may reproduce in high quality habitats. Conversely, females in marginal habitats may not produce young prior to their seventh year. Food availability prior to the denning season has a significant bearing on litter size. Cubs are born in winter dens in January and February. Although two or three cub litters are most common, litter sizes range from zero to four, depending on the age and condition of the female. Cubs are born in a helpless state. Measuring about eight inches in length and weighing eight to twelve ounces, they develop and grow rapidly largely because of the richness of a mother bears milk. The sex ratio at birth is usually one male to one female.

Mother and cubs leave the den in April or May when the young weigh from four to eight pounds. The cubs stay with their mother through the first year, which includes sharing a winter den. In mild winters, with residual food sources available, it is not uncommon for the family unit to remain active through the winter. They emerge with her again in the spring, and live with her until the summer when the family unit dissolves. Male offspring tend to disperse, while females remain nearby. When the family unit dissolves, the female then goes back into estrus, breeds, and repeats the cycle.

 
Hibernation

Based on the Tensas and Atchafalaya River Basin studies in Louisiana, the onset of denning occurs from late November to early January. Activity, movement, and home range generally decrease rapidly during this period as bears enter "pre-dens" or nests, or enter the den where they will spend the winter. Black bears are not true hibernators. They go through a winter dormancy period in which their heart rate and temperature drops below normal, which helps them survive food shortages and severe winter weather. During the winter "sleep" bears do not eat, drink, urinate, or defecate. Waste products are recycled through unique metabolic and physiological processes and there is no degenerative bone loss during dormancy. Black bears exhibit varying degrees of lethargy while denning, but most can easily be aroused if disturbed.

Denning activity is influenced by a number of factors: food availability, age, gender, reproductive condition, photoperiod, and weather conditions. Generally, pregnant females are the first to den and males the last. Factors contributing to interruption of the denning period or the changing of den sites during a given winter include human activity, rapidly fluctuating water levels, fluctuating extremes in weather conditions, and the lack of concealment of ground dens. Data collected by monitoring denning behavior indicate bears are more active in winter months in the lower Mississippi River Valley than at more northern latitudes; however, no studies have been done in Alabama.

For some bears, usually males, winter inactivity may be nothing more than bedding for a few days or weeks in one area before moving to new bedding sites. Pregnant females, the first to seek den sites, usually choose sites that are more secure and inaccessible than those typically selected by males. Females prefer large, hollow trees, as these provide dry, secure, and well-insulated cover, but will also den in brushpiles and thickets.

 
Movements

Monitoring bear movements has revealed that bears are more active from dusk through dawn, although daytime activity is not unusual and varies somewhat by season. Home range sizes vary from year to year, and from season to season, depending on population density, food availability, sex, age, and reproductive status. Home ranges for males may increase during the mating season in summer and both male and female bears move extensively in fall when foraging to put on winter fat reserves.

Bear activity revolves around the search for food, water, cover, and for mates during the breeding season. Male black bears move much greater distances than females, often covering 2 to 8 times the area of females. Some adult male bears in the Tensas basin ranged up to 35 miles from their capture site. Estimates of average annual home range sizes indicate adult males use 20,000 acres and adult females use 5,000 acres, although individual home ranges can vary widely. For example, one adult male in the upper Atchafalaya Basin ranged over 85,000 acres.

Bears often utilize "daybeds" under forested cover. These sites are usually shallow, unlined depressions scratched in soft ground or leaf litter. Mothers with cubs often bed at the base of the largest tree in the area. The female sends the cubs up the tree if she senses danger and either climbs the tree with them, remains at the base of the tree or exits the area alone. Sometimes bears will rest above ground in the crown or lower branches of a tree.

Older adult males exert social pressure on younger bears, especially during the spring and summer breeding season, forcing them to disperse to other areas. Dispersal of bears, especially young males, puts them at considerable risk. Their movements take them to unfamiliar areas, often those inhabited by humans. In their attempt to locate a new home, they cross roads and highways, increasing the chances of being hit by motor vehicles, and will likely cross areas inhabited by humans. This creates potentially dangerous situations for both humans and bears. Because of the stress and increased human interaction, dispersing bears have a reduced chance of survival.

Data from studies of radio-collared bears and observation of bear sign document that uncleared drains, ditches, bayous, and river banks are frequently used to traverse open land when moving from one forested tract to another. Travel corridors are important to the movements of adult bears and the dispersal of juveniles through agricultural lands, particularly when they are residing in separate tracts of forested lands or in a severely fragmented forest. Females are especially reluctant to move from one forest block to another if there is no vegetative cover linking the 2 areas. Drainage ditches lined with trees and brush, even as narrow as 30 feet wide, are used by bears to pass through open agricultural areas. Based on comparative data, this may be a minimum width for a viable corridor; however, a good rule of thumb would be "the wider the better."

 
Food Habits

Classified as a carnivore (i.e., meat-eating animal) by taxonomists, Louisiana black bears are not usually active predators and rarely prey on vertebrate animals. There are many stories of bears feeding on nutria and other furbearers caught in traps during the days when fur trapping was a viable vocation. There have been no reports of Louisiana black bears preying on livestock or pets in recent history. Bears are better described as opportunistic feeders as they eat almost anything that is available, thus they are more typically omnivorous.

The growth rate, maximum size, breeding age, litter size, and cub survival of black bears are all linked to nutrition. Bears spend a considerable amount of time foraging for food, using their keen sense of smell to locate food sources. Feeding signs are usually evident in areas of bear activity, including torn logs, broken saplings, clawed trees, and trampled food plants. Bears utilize all levels of the forest for feeding; from the forest floor to the treetops. Excellent climbers, they can gather foods from treetops and vines.

After emerging from dens in spring, bears may initially be in a "semi-fasting" state as they continue to utilize remaining fat reserves. Food is relatively scarce during this period and weight loss is often more rapid than during denning. Succulent vegetation is first utilized for food and then foods such as residual hard mast (acorns, pecans, etc.), agricultural crops, and insects are consumed. With the arrival of summer, soft mast including dewberries, blackberries, wild grapes, elderberry, persimmon, pokeweed, devil's walking stick, thistle, and palmetto will become staples in the diet. In the fall, hard mast, such as acorns and pecans, is a particularly important fat and carbohydrate-rich food source that provides the fat reserves necessary for bears to enter the denning period in proper health. Bears exhibit their most rapid weight gain during fall, thus, hard mast is considered a critical food source at this time.

Agricultural crops supplement natural foods and can be very important food sources throughout the year, especially in areas of extremely fragmented habitat and high bear density. For example, corn is an important forage crop for the large number of bears inhabiting some agricultural areas in Louisiana. Bears will readily take advantage of food opportunities provided by man. Besides crops from both commercial and residential plantings, bears can get into trouble for getting into garbage and pet foods. In areas where bears are present, it is important for measures to be taken to prevent access to these tempting foods (see Living with Bears chapter).

 
Habitat Requirements

The remaining black bears in Alabama do so primarily in relatively large contiguous areas of bottomland hardwood habitat. The ingredients of prime black bear habitat include escape cover, dispersal corridors, abundant and diverse natural foods, water, and den sites. Because bears are adaptable, habitat generalists, a well-managed, productive forest can reliably provide the essentials of good black bear habitat. High quality escape cover is especially critical for bears that live in fragmented habitats and in close proximity to humans. Black bears are adaptable and can thrive if afforded areas of retreat that ensure little chance of close contact or visual encounters with humans. The thick understory typical in managed bottomland hardwood forests provide such natural cover. The quality of escape cover can be enhanced when slash and vegetative growth resulting from prescribed timber management practices such as shelterwood cuts, intermediate thinnings, and small elongated clear-cuts are combined with natural understory thickets.

Forest management practices also encourage food production for bears. Grasses, thistles, blackberries, pokeweed, and several fruiting vines are common in managed forest habitats. Elderberry, devil's walking stick, French mulberry, red mulberry and wild grapes all benefit from scattered openings in forest canopy. Rotting wood from decomposing logging slash harbors protein-rich, colonial insects like ants and termites, which are sought by bears during most of the year. Additional foraging opportunities are made available by the maintenance of small, scattered permanent wildlife openings in or adjacent to the forest. Natural vegetation, cultivated grains and forage crops (e.g., wheat, oats, rye, corn, clover), and plants found along the edge of forest openings (e.g., blackberries, dewberries, pokeweed, elderberry, devil's walking stick) are beneficial to bears.

Black bears use heavy cover for daybed and den sites.  Cavity trees are especially important in seasonally flooded areas. In Louisiana, over 90% of bears den in tree cavities on the White River NWR, and on the Tensas River NWR, where some winter flooding is common, about 70% of the bears den in trees. A Federal Rule in the listing of the Louisiana black bear as a threatened species specifically states that den trees, den tree sites, and candidate den trees in occupied habitat are to be protected. Candidate den trees are considered to be bald cypress and tupelo gum with visible cavities, having a minimum diameter at breast height (dbh) of 36 inches, and occurring in or along rivers, lakes, streams, bayous, sloughs, or other water bodies. However, studies throughout the region frequently document other tree species used as den sites (e.g., green Ash, American elm, sweetgum, water hickory, overcup oak) that are not necessarily over water.

 
 
Alabama Black Bear Alliance © 2006