Black Bear
The name black bear can be misleading. Black bears actually have several color phases other than black, including brown (not to be confused with grizzlies, also known as brown bears), blond and cinnamon. They may also have tan or light coloration on the muzzle and chest.
About
Black bears are large and stocky and have a short tail. The ears are small and rounded on a relatively small head supported by a strong, muscular neck. Their powerful limbs each have five toes and five short, curved claws for digging and cutting. Their front feet are about as long as they are wide, but the hind feet are long and narrow and resemble a human foot.
Black bears have an omnivorous diet, meaning they eat both plants and animals. They consume grasses, roots, flowers, leaves, berries, insects, fish and carrion. Nonetheless, black bears are strong predators and will kill elk calves and deer fawns. In spring, they consume emerging plants and carcasses of animals that have died during the winter. Fruits dominate the diet in summer, and both fruit and mast, especially acorns, constitute most of the fall diet. Black bears need to store enough fat to last through the winter season when food is scarcer. On average, they consume about 20,000 calories each day during the fall.
Life History
ABlack bears are characterized as shy, secretive animals possessing considerable curiosity and displaying high levels of intelligence and exploratory behavior. Black bears are generally active in the early morning and late evening; they may alter their activity patterns to exploit sources of artificial food, becoming nocturnal at campgrounds and dumpsites. Nuisance activities are nearly always associated with artificial food sources, including beehives, campgrounds and livestock. AZGFD is committed to helping people learn how to behave responsibly and coexist safely in black bear habitat.
Black bears are normally solitary animals except for family groups (mother and cubs), breeding pairs and congregations at feeding sites. Black bears are known to move long distances, up to 100 miles, to exploit isolated pockets of food. The mobility of black bears sometimes leads them to appear in uncharacteristic habitats and to return from long distances after being moved. Most Arizona black bears hibernate from November through March, during which time they reduce body temperature, heart rate and metabolic function while still remaining somewhat alert in the winter den.
Cubs are typically born during December and January in winter dens, usually in pairs, but larger litters are not uncommon. The cubs are very small and helpless at birth. Cubs emerge from the den in April and stay with their mother through the first summer and fall, denning with her their second winter. Female black bears in Arizona typically reach reproductive age in their fourth year and usually breed every other year. Normal reproductive cycles in black bears may be adversely affected by poor food production during drought and resultant poor physiological condition. Black bears are relatively long-lived animals, with some individuals exceeding 20 years of age. The low reproductive potential of this species is an important management consideration.
Distribution and Abundance
Black bears are the most common and widely distributed of the three North American bears. Historically, black bears occurred in all forested habitats in North America, including Mexico. The species has been extirpated from many Eastern and Midwestern states but still occurs in 38 states, 11 Canadian provinces and seven Mexican states.
Black bears occupy about 10,000 square miles of nontribal lands in Arizona, most of which are in the north and eastern half of the state. In Arizona, black bears are found in most woodland habitats, including pinyon-juniper, oak woodland, coniferous forest and chaparral. Relative densities of black bears in Arizona are highest along the Mogollon Rim, in the Mazatzal Mountains in central Arizona and in the White and Pinaleno mountains in eastern Arizona. AZGFD reports a stable to increasing black bear population, with an estimated 5,800 black bears in the state.
Wildlife managers use harvest data, specifically the sex and age composition of the annual harvest, to monitor long-term population trends and ensure a science-based approach to regulating black bear harvest. These data are monitored to ensure the population maintains an appropriate composition of adults, subadults and juveniles of both sexes necessary for sustainable populations. To collect harvest data, AZGFD requires hunters who harvest a black bear to physically present the skull and hide, with proof of sex attached, to AZGFD within 10 days of harvest. During this inspection, a premolar tooth is removed from each harvested black bear to accurately determine its age using cementum annuli analysis, similar to counting tree rings. Managers also collect tissue samples that may be used to genetically identify individuals and evaluate metapopulations, connectivity and dispersal, as well as for other investigative purposes. AZGFD uses harvest data and adaptive management, along with information acquired through research, to guide hunt management strategies and inform land management decisions such as transportation design, alternative energy projects, and urban and rural development planning.
Management and Research
Black bear management has a long and complicated history in Arizona. Classification of black bears fluctuated back and forth in the early to mid-1900s, from a predatory animal with an open season and no restrictions to a big game animal with designated seasons and harvest limits. Since 1968, black bears have been classified as big game and are considered an important part of Arizona’s fauna. They are managed for a sustainable population, as are all big game species. Regulated hunting is one tool wildlife managers use to keep predator and prey populations balanced and reduce adverse impacts on any of those populations.
Black bear hunting in Arizona is managed with female harvest limits, which close the black bear hunting season in a particular hunt area when the limit has been reached. Female harvest limits are established using a sustainable harvest rate applied to the estimated abundance for each hunt area. The season is nine months long, with a summer closure when research shows that mountain lion births are at their peak. Sows with cubs and cubs with sows are protected by state statutes, and reports of any illegal harvest are investigated thoroughly by wildlife managers. Successful hunters are required to report their harvest within 48 hours and have it physically checked by an AZGFD employee within 10 days for identification of age and sex and the collection of important biological information. Wildlife managers use these data to closely monitor harvest and ensure a sustainable population. Adult female survival tends to be the most influential demographic parameter influencing black bear population growth. Therefore, female harvest is closely monitored and serves as a parameter to reduce harvest limits or season length.
AZGFD is actively researching black bears across the state to estimate survival rates and evaluate cause-specific mortality. These data will be useful in building a new population model to estimate abundance. Additionally, researchers will estimate reproductive success of female black bears to inform the population model, investigate denning chronology for males and females along a latitudinal gradient in Arizona, which could influence the timing of hunting seasons, evaluate seasonal and annual black bear movements, estimate annual home range sizes and assess diseases that can affect black bears. Previous research on black bears in Arizona has included estimating densities and assessing demographics in different habitats, investigating the use of noninvasive sampling to estimate abundance, and evaluating demographic and spatial responses to wildfire.