Black Bear: There are eight kinds of bears (Ursus) in the world, but I chose the North American Black Bear (Ursus americanus). I will cover general information about the bear, such as their size, weight, color, and food. However, I will mainly concentrate on the hibernating cycle of the Black Bear.
There are 400,000 to 750,000 black bears in North America, and they weigh between 130 and 660 pounds with a body length of 50 to 75 inches. Their colors vary from black, chocolate brown, cinnamon brown, pale blue (known as glacier bears) to white. Black bears often have a brown muzzle and may have a lighter color patch on their chest. Their feet are equipped with strong, highly curved claws. They are omnivores, eating nuts, berries, fruits, insects (especially ants), deer and moose fawns, carrion, and, in coastal areas, spawning salmon. Their habitat includes forests with occasional open areas such as meadows.
They occupy all of Canada, starting from the tree line and going south. They live in all provinces and territories except Prince Edward Island, where heavy deforestation has occurred, and preferably away from brown bears (larger competitors). The only main risk for black bears is poachers who sell their parts illegally to the Asian medicinal market. In northern areas of Canada, the bear undergoes a remarkable metabolic transformation as it prepares for hibernation. Hibernation is an energy-saving process bears have developed to let them survive for long periods when there is insufficient food available to maintain their body mass. When they stop eating and become increasingly lethargic, the bear will enter a cave, dig out a den, or hole up in a dense brush pile, hollow log, or tree cavity and hibernate.
Right before it does this, the bear starts to gain weight so it can survive the long months ahead. It can gain as much as 30 pounds per week. The bear hibernates for four to seven months. When it’s in a hibernating state, the bear’s heart rate drops from between forty to seventy beats per minute to only eight to twelve beats per minute. Its metabolism slows down by half, and its body temperature reduces by 3 to 7 degrees Celsius (5 to 9 degrees Fahrenheit).
Also, its body does not release any waste like urea or solid fecal waste, but instead, it is recycled into usable proteins. During the hibernation period, adult males and adolescent bears lose between 15% and 30% of their weight, while a female cub with a newborn loses as much as 40% of her weight. Most black bears vacate their winter dens over a one to two-month period starting in April or May. Both the climatic conditions (snow cover and temperature) and physiological factors such as the bear’s age, the status of its health, and its remaining fat reserves affect the time it comes out. Normally, adult males emerge first. Females with newborn cubs are usually the last ones to leave their den and continue with their life cycle.
