BEAR FACTS
Bronze Bear Statue
Bears are carnivoran mammals. They are widespread, and appear in a wide variety of habitats the Northern Hemisphere and parts of the southern hemisphere. They are found on the continents of North America, South America, and Eurasia. Characteristics of modern bears include large bodies, stocky legs, long snouts, small rounded ears, shaggy hair, plantigrade paws with five claws, and have short tails.
Polar bears are mostly carnivorous, and pandas’ mostly herbivorous. The other six species are omnivorous with varying diets, with the exception of courting individuals, while mothers with their young, bears are typically solitary animals. They can be diurnal or nocturnal and have an excellent sense of smell. In spite of their heavy build and awkward gait, they are excellent runners, climbers, and swim quite well.
Bears use caves and logs as their dens during the winter for a long period of hibernation, that can last for up to 3 or 4 months. They have been pursued for their meat and fur since ancient times. In modern times, bears are under increasing threat from habitat loss and the illegal trade of bear parts.
Six species of bears are considered vulnerable or endangered, and even those categorized as least concern, such as the brown bear, face the danger of local extinction in certain areas. While poaching and international trafficking of the most endangered populations are prohibited, these activities still take place.
Most bears are adaptable eaters, taking in more plant material than animal products, and are believed to have descended from a common ancestor that primarily thrived on a low-protein diet.
They have a diverse diet that includes a range of foods such as leaves, roots, berries, insects, carrion, fresh meat, and fish, and their digestive systems and teeth are designed to handle this variety. At one end of the spectrum is the largely plant-based giant panda, at the other end is the mainly meat-eating polar bear. However, all bear species will consume any available food source depending on the situation.
When looking for plants, bears tend to eat them at their most nutritious and digestible stages, typically avoiding older grasses, sedges, and leaves. As a result, in northern temperate areas, foraging and grazing occur more frequently in early spring and decrease as the season advances.
Bears are capable of identifying when fruits are ready to be eaten. They often search for berries in bushes or higher up in trees, aiming to increase their intake of berries over leaves. In the fall, certain bear species consume significant quantities of naturally fermenting fruits, which influences their behavior. They may roam extensively in pursuit of other food options. Due to their powerful digging skills, brown bears frequently consume roots.
Recognized as efficient foragers and opportunistic thieves, they frequently steal food caches from rodents and take carcasses from other animals. They enter a state of hibernation, making it essential to gain weight, which provides energy during their winter sleep. A brown bear is capable of eating 90 pounds of food and can add as much as 6 pounds of fat each day prior to retreating to its den for the winter.
Bears sometimes rely on visual cues for communication, such as rising on their hind legs to showcase their size. The chest markings seen in some species may amplify this intimidating display. A piercing gaze can indicate aggression, and the facial characteristics of spectacled bears and giant pandas may serve to emphasize their eyes during conflicts.
Bears might approach one another with a rigid-legged walk and heads held low. Dominance displays in bears include facing one another, exposing their canine teeth, twisting their snouts, and extending their necks. A bear that is in a submissive position may respond by turning to the side, averting its gaze, lowering its head, or by sitting or lying down.
Bears communicate through scent by urinating on and scratching trees and other surfaces. This action is usually accompanied by clawing and biting the area. Bark might be thrown around to make the marking location more noticeable. Pandas identify their territories by marking surfaces with urine and a waxy substance from their anal glands. Polar bears leave their scent through their footprints, allowing others to trace their movements in the vast Arctic landscape.
Bears exhibit various reproductive behaviors, such as polygyny, promiscuity, and serial monogamy. During the mating season, males become attuned to the proximity of females, while females demonstrate a greater willingness to allow males to approach. A male bear may spend a few days or even weeks with a female, depending on the species, in order to evaluate her readiness for mating.
The gestation period typically lasts between 6 to 9 months and involves a stage of delayed implantation, often resulting in litters of up to four cubs. Although giant pandas can give birth to twins, they can only care for one cub, leading the other to die. In populations living in northern areas, births take place during the winter dormancy. Cubs are born blind and defenseless, with minimal fur coverage, relying entirely on their mother for warmth.
The milk produced by female bears is rich in fat and contains antibodies, allowing cubs to nurse for up to a year after they are born. At approximately 2 to 3 months of age, cubs can begin to follow their mother out of the den. Generally, they walk alongside her, but sloth bear cubs may also ride on their mother’s back. Male bears do not take part in raising the young. Infanticide, which occurs when an adult male kills the cubs of another bear, has been noted in polar bears, brown bears, and American black bears, although it has not been reported in other species of bears. Males may kill the young to trigger the female’s estrus cycle. When in danger, cubs may flee, while the mother will defend them, even at the risk of her own life.
In certain species, young may become independent by the following spring, though some may stay with their mother until she successfully mates again. Bears generally reach sexual maturity shortly after they leave their initial home, usually between the ages of 3 to 6 years, depending on the species. Male Alaskan brown bears and polar bears can continue to grow until they’re roughly 11 years old. The lifespan can also vary among species, with brown bears living on average about 25 years.
During the winter months, bears that live in colder regions, like the American black bear and the grizzly bear, go into a form of hibernation. While in hibernation, a bear’s metabolic rate slows down, its body temperature decreases slightly, and its heart rate drops from around 55 beats per minute to only 9. Generally, bears remain in a deep sleep throughout the hibernation period and can survive the entire season without consuming food, water, or needing to urinate or defecate solid waste.