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Black Bears IN BRITISH COLUMBIA Ecology, Conservation and Management Ministry of Environment, Lands and Parks Ten thousand-year-old skeletons in caves on Vancouver Island indicate that black bears arrived soon after glaciation. INTRODUCTION Asiatic black bear, sun bear, and sloth bear in Asia. The black bear (Ursus americanus) is the smallest and Only 18,000 years ago, British Columbia was com- most widely distributed member of the bear family pletely covered with ice and black bears were relegated found in North America. In British Columbia, black to at least two refugia: one in what is now the United bears inhabit all areas of the province except most States and one near the urban cores. They Queen Charlotte Islands. British Columbia are relatively Following glacial melting, numerous and bears gradually spread back has more races of tolerant of human north and also re-colonised activities and as a coastal British Columbia black bear than result are the most from near the Queen commonly encoun- Charlotte Islands. Ten thou- any other part tered large carnivore sand-year-old skeletons in in the province. caves on Vancouver Island of Canada. Black bears are indicate that black bears not always black, arrived soon after glaciation and were larger than and this variation is modern-day black bears. Scientists believe that bears most apparent in on Vancouver Island and the Queen Charlottes have British Columbia. retained more of their ice-age characteristics than Other colour phases mainland bears because of a long period of isolation Jared Hobbs that occur in British from continental populations. Columbia include cinnamon, brown, and blonde. A British Columbia has more races of black bear than white-coloured morph, called Kermode or Spirit Bear, any other part of Canada. This is attributable to the is reported most frequently on the north-central coast. arrival of bears that had differentiated in glacial refugia, The blue phase, or “glacier” bear, is sometimes seen in the variety of terrain and climate in the province, and the extreme northwest corner of the province. SUBSPECIES (RACE) RANGE AND PHYSICAL CHARACTERISTICS Ursus americanus cinnamomum Most of British Columbia east of the Coast Range. Is generally EVOLUTION AND larger, with narrower teeth than U. a. altifrontalis. The brown colour phase is common. APPEARANCE Ursus americanus altifrontalis Coastal race ranging from Oregon to Bella Coola, western The bear family, Ursidae, Tweedsmuir Provincial Park, east into Manning Provincial contains eight species on Park and Lillooet. Primarily black-phase bears. four continents and Ursus americanus vancouveri Insular race restricted to Vancouver Island and larger adjacent includes the giant panda. islands; large like U. a. carlottae but has smaller teeth. Primarily Three species of bears – black- phase bears. grizzly (brown), polar, Ursus americanus carlottae Insular race restricted to the Queen Charlottes; massive skull, and black – occur in large molars; only black phase. Ursus americanus kermodei Restricted to the coastal mainland of British Columbia from North America, the latter Burke Channel to the Nass River and most adjacent islands. nowhere else. Other Includes white and black colour phases. The white colour species include the phase is most common on Princess Royal and Gribbel Islands spectacled bear in (about 10% of bears) but is seen occasionally throughout the South America, and the range of Kermodei. Ursus americanus emmonsii Limited to the extreme north-west of the province; primarily found in Tatshenshini Provincial Park and adjacent Alaska; includes the rare glacier or “blue” bear. the isolation of some bear populations on our forestland across the province. Its natural range islands. Although the differences are not great, they includes Vancouver Island and most coastal islands illustrate biodiversity in the making. to the north, including the Queen Charlottes (Haida Black bears have a chunky body, small black eyes, Gwaii). Although generally absent from alpine, grass- a broad head, rounded ears, a short tail, and a fine, land, and heavily settled landscapes, black bears often long pelage. Typically, they have uniformly black fur, occur close to the fringes of communities and some- except for a tan muzzle and a white V on the chest. times wander into them. The feet are flat-soled (plantigrade), with naked pads The current estimate of the black bear population and five toes with relatively short curved claws. Adult in British Columbia is 120,000–160,000. This is size, and particularly weight, varies greatly according about one quarter of all black bears in Canada. Bear to sex, season, food supply, and geographic area. numbers are higher in wet climatic zones, where vege- Adult males measure about 60 to 90 cm in shoulder tation is more plentiful, than in dry regions, and height and 130 to 190 cm coastal bear densities are higher in length and weigh 80 to PAW PRINTS because of access to spawning In coastal British 300 kg. Females are smaller, salmon. Although bear numbers weighing 40 to 140 kg. vary from year to year and habi- Columbia, almost Black and grizzly bears tats available to them are slowly sometimes look similar, shrinking due to land develop- all black bear dens but grizzlies are usually ment, the species is not currently larger and are seldom rare, threatened, or endangered are in or under completely black. Grizzlies in British Columbia. have a prominent shoulder large-diameter hump, which is lacking in LIFE HISTORY black bears, and a dish- Black bears have low reproduc- trees, snags, logs or shaped face instead of the tive rates compared to many straight facial profile of the other mammals. Females usually stumps, and may black. Grizzlies have much longer claws that are don’t reach sexual maturity until adapted for digging, whereas the shorter, curved claws four years of age and breed only be up to 25 m of black bears are well suited for tree climbing. every two to three years after that. In areas of abundant food, above the ground. DISTRIBUTION AND ABUNDANCE they may reach maturity sooner. Black bears, estimated to number well over half a Where food is scarce females might not bear their first million, range over a vast area, from the Arctic tree- litter until they are six or seven years old. Although line south to Florida and northern Mexico, but are some males can breed when they are one and a half sparse or absent in large parts of the United States. years old, in most populations males don’t mature In Canada they occur from coastal British Columbia sexually until age five or six. Black bears can live for to Newfoundland. 25 to 30 years in captivity, but their life-span in the One of the most widely distributed mammals wild is usually much shorter. in British Columbia, the black bear is found in Black bears in British Columbia usually mate from early June to mid-July. However, in a phenomenon called delayed implantation, the embryo does not implant in the uterus and begin developing until October or November. Cubs are born in January or February, during hibernation. Black bears usually have PLENTIFUL two cubs, but litter sizes vary from one to five. At MODERATE birth, cubs are hairless, blind, and weigh about 400 g. FEW They nurse while the mother continues hibernating ABSENT and weigh 3 to 5 kg when they leave the den in spring. Cubs stay with their mother their entire first year and sometimes longer. During that time, she protects them and teaches them how to survive. They are weaned between July and September and hibernate with their mother the first winter. By the middle or end of their second spring, cover. Black bears, especially females with cubs, avoid they are on their own. The open areas when moving from one feeding site to mother drives the cubs away another. Secure travel routes are therefore important when she is ready to breed for linking foraging areas. Home ranges may shift in again. At first they stay within response to weather and the availability of seasonal her home range, and the food and often overlap those of other black bears. mother may allow female cubs While related females are known to share home to set up home ranges that ranges, black bears are mostly solitary. The only com- overlap hers. Male cubs usually mon social groups are the sow with her cubs and the stay within their mother’s mating pair, but the latter bond is quite temporary. home range for only a short Groups of bears at food sources like landfills or time and then disperse to find salmon spawning streams usually lack social cohesion. Tom Hall a home range in a new area. A bear’s nutritional state is important because it Hibernation is an important survival strategy for influences reproductive success, survival, and hence bears in regions such as British Columbia where their the abundance of bears. Black bears are classified as main foods – green vegetation, berries, salmon, and carnivores (meat eaters), insects – are not available in winter. Black bears typi- but they are omnivorous To conserve energy, cally hibernate for three to five months on the south (“everything-eaters”) and coast and for longer periods (probably five to seven consume a variety of plant black bears seek out months) in the interior and the north. Females, partic- and animal foods. Black ularly the pregnant ones, hibernate longer than males. bears use different foods in concentrated food In coastal British Columbia, almost all black bear different seasons and seek dens are in or under large-diameter trees, snags, logs, out low-fibre, easily sources, such as or stumps and may be up to 25 m above the ground. digestible foods. Vegetable Bears in the interior also use tree cavities, but if big matter forms the bulk of spawning fish and trees are not available, the bears often den in rock cavi- their diet, particularly in ties, under brush piles, or in holes dug into the ground.