Bears are categorized as carnivoran mammals, belonging to the Ursidae family. Presently, there are eight surviving species, widely distributed in the Northern Hemisphere, as well as parts of the Southern Hemisphere. Their large-sized, hairy bodies, long snouts, round ears, and stocky legs are some of their identifying features.
Size: They show sexual dimorphism when it comes to size, with the males being larger than their female counterparts. The polar bear, the largest of the surviving species, has a body length of 8 to 10 feet (2.4 to 3.04 meter). The sun bear, the smallest among them, is 3.25 to 4.58 feet long (0.99 to 1.39 meter).
Weight: The adult
males weigh around772
to1543 lb.The sun bear weights 55 to 143 lb. There
is a fluctuation in their weight, particularly in those living in the arctic
and temperate regions. During summer and autumn there temperature increases as
fat reserves build up in their body, while in winter, the weight reduces.
Color: The color varies from one species to the other. The polar bear looks white (though that is not its actual shade). The sun bear has a dark brown, grey, or black body with markings of orange, white, or yellow. Whereas, the spectacled bear has a dark brown or black furry body.
Body: They are
massive in appearance with a broad head, massive frames, and extended jaws.
Ears: Their ears
are small and round.
Eyes: They have
small, black eyes.
Legs: The bear
has four legs, two at the front and two behind, all of which are muscular,
straight, and stocky.
Paws: Their front
paws are larger than the ones at the back.
Claws: They have
non-retractable claws used for a wide variety of reasons. Their hind claws are
not as big as those on their front feet, making it difficult for them to climb
trees.
Teeth: They have
42 teeth in total, four canines, twelve incisors, ten molars, and sixteen
premolars. The canines are large, long, and pointed, though they have little
function. The molars possess flat crowns, while the premolars remain
undeveloped, with some even missing.
Tail: Their short tails are a contrast to the long, thick, graceful ones they had in the past.
Distribution
They have a wide range, majorly distributed throughout North
and South America, Europe, and Asia. However, certain species remain confined
to a particular location. E.g., the
polar bear inhabits regions around the Arctic Ocean, and the spectacled bear
dwells in the Andean region of South America.
Where Do Bears Live
The bear’s habitat is diverse, as they inhabit the steppes,
prairies, montane grasslands, and tropical low land forests. Polar bears are
often seen spending a significant part of their time living on sea ice.
How Long Do They Live
The lifespan varies from one species to the other. The brown
bear lives for about 25 years, while the black bear has a life expectancy of
approximately 30 years.
What Do They Eat
Bears are omnivores, and their diet comprises of anything from roots, leaves or berries, to fresh meat, carrion, as well as insects. Fish also serves as an essential food source for some, like the brown bear, who does not leave any opportunity to capture salmon. There is, however, an exception, as the polar bear is mostly carnivorous, while the brown bear is herbivorous feeding on bamboo.
How do they capture their prey
The hunting techniques differ from one bear species to the
other. While capturing a fish, most of them jump into the water taking their
prey using their front paws or jaws. For rodents, they prefer digging the small
creatures out of their den and devour them. The brown and black bears are known
to target bovids as well as deer, particularly the younger and weaker ones. The
polar bear hunts seals, by ether seizing them from the ice or even attacking
their dens. A mother teaches her cub predatory behavior right from the start.
Behavioral Characteristics
Bears are solitary animals, considered as the most asocial among all carnivoras. They are only seen in small groups when the mother tends the young, or they all go together in search of food.
They may be diurnal or nocturnal. Species like the American Black and Brown bear being mostly active throughout the day. The sloth bears appear during the night. However, the females of this species feed their cubs in the day to avoid any competition from nocturnal predators.
These mammals are increasingly curious, often indulging in inspecting noises, smells, or anything that is going on around them.
They are efficient swimmers and runners despite their bulky appearance.
Bears are also great climbers, with species like the black bear often going up to escape from any impending danger. However, the grizzly bear remains an exception in this regard all because of its long claws.
Most of them, particularly the brown, black, and grizzly bears hibernate for about 100 days in winters since food is scarce and the weather gets cold.
They can locate carcasses even if they are many kilometers away from it all because of their strong smelling instincts.
These mammals demarcate their territory by rubbing their bodies against trees as well as other objects so that their scent may spread and warn others of their ownership. The pattern, however, varies from one species to the other. The pandas use their urine, alongside a waxy substance for marking their domain. The polar bear resorts to chemical communication by leaving their scents on the tracks they walk on so that each would remain aware of the other’s whereabouts.
They have a great memory, with species like the grizzly bear remembering the location where they had previously found their food source.
The presence of strong jaws helps them in crushing and biting the strong stems of certain plants.
Adaptation
Thick layers of fat are present below their skin, helping them to withstand cold temperatures.
There small, and round ears minimize chances of heat loss, preventing cold water from entering into their ears.
Bears possess color vision, thus being able to discriminate between different shades, thus making them adept in distinguishing fruits from ripe nuts.
They have a reflective membrane behind their eyes known as tapetum lucidum, which helps improving night vision.
They have a large olfactory bulb, five times bigger than that of humans, and a highly developed nose with many tiny muscles, which contribute to their keen sense of smell.
Their digestive system has one stomach, with short undifferentiated intestine devoid of any cecum. This structure helps the mammals to digest the complicated kinds of foods, especially the vegetarian diet they mostly eat.
Reproduction and Mating
The bears adopt polygyny (male has multiple females), serial monogamy (individual has a single partner throughout his life), or promiscuity (being engaged with different partners) mating process. In the course of the breeding season a male pays several visits to the female’s den to know her better and even resists other males from coming in contact with their prospective mates. The period of courtship lasts for a short span, with mock fighting, wrestling, vocalizing, and hugging observed amongst pairs of certain Asian species. Mating, which induces ovulation, lasts for about 30 minutes, though this span varies from one species to the other. The gestation period lasts between six and nine months, with the litter size being around four cubs.
The cubs are blind at birth, depending on the mother bear for warmth. They drink their mother’s milk for about a year since it has a high amount of antibodies and fats. The young ones start following their mother out of her den by the time they are 2 or 3 months of age. Mothers are extremely possessive and protective about their babies, defending them even by putting their life at stake.
Hibernation
These mammals, notably the grizzly and American black bear, hibernate during the winter months, for about 100 days, mostly to get respite from cold. Besides slow metabolism, there is a decrease in body temperature. Their heartbeat per minute goes down from 55 to just 9. A fecal pug (hardened mass of feces) develops in their colon, getting expelled in spring after they wake up from slumber. During this phase, the females birth their cubs and are awaken form sleep for the process.
Communication
They communicate through a host of vocal as well as nonvocal sounds.
Peaceful situation
(mother-baby interaction or courting): Grunting, chuffing, and tongue
When stressed:
Huffing, blowing, sorting or moaning
When alarmed or
excited: Barking-like sound
As a warning: Lip-popping
and jaw-clicking
During aggressive
encounters: Growl, chattering or teeth, bellowing and roaring
Cubs vocalize through humming when being nursed. However, if
in distress, they would bleat, squeal, scream, or bawl.
Non-vocal communication includes standing upright, staring, showing their canine teeth, stretching their neck as well as twisting their muzzle.
Though they do not
have too many predators, their biggest threats come in the form of humans who
may indulge in hunting these animals. Their territories are even occupied by
mankind for agricultural and other purposes which may result in confrontation. The
IUCN enlists six of the bear species as vulnerable. The African black and brown
bear, which are under the least concern category, could even have chances of
being extirpated in certain areas. Several laws have been implemented worldwide
to conserve their habitats. The Sichuan Giant Panda Sanctuaries houses many
wild pandas (30% of their population). Specialized organizations have developed
worldwide for conserving several bear species like the Vital Ground (brown
bear), Wildlife SOS (sloth bear), Moon Bears (Asiatic Black Bear), and Black
Bear Conservation Coalition (North American Black Bear).
Bear-FAQs
1. What are male and
female bears called?
Male bears are known as boars, while the females are
referred to as sows.
2. What is a baby
bear called?
A cub.
3. What are bears
related to?
Being a part of the Caniformia suborder, bears are closely
related to canids (dogs, coyotes, wolves, dingoes, jackals, and foxes),
musteloids (carnivoran mammals) and pinnipeds (family of seals and other
carnivorean aquatic mammals).
4. Are bears related to pigs?
No, as pigs belong to the Suidae family, sharing a closer
relation to cattle, deer, giraffe, and camel.
5. What is the meaning of bear?
It derives its name from “bera,” an Old English word, literally translating to the brown one. There are other etymologies surrounding the animal as it also means a wild animal and a brave warrior.
6. What is the Latin name of bear?
Their family name Ursidae, comes from the Latin words Ursus
(he-bear) and Ursa (she-bear).
7. What is a bear’s home called?
A den
8. How long have bears been around?
For over 30 million years.
Interesting Facts
Because of their intense physical appeal, bears have found a prominent place in mythology, arts as well as host cultural aspects.
In Ainu and Chinese culture, bear worship was prevalent whereas Koreans and Siberians considered them as their forefather’s spirits.
Certain species of bear are known to attack humans, especially if they feel startled, or even while defending their food or young ones.
In ancient times, bears were trained for a whole lot of entertainment like baiting and dancing.