Many people have asked me recently about the different physical characteristics of the three species of bears found in North America. While there are many similarities, there are also some major differences.
There are three types of bears found in North America, the American black bear, the brown grizzly bear, and the polar bear.
Height and Weight
The American black bear is the smallest bear species in North America. They stand up to 3 feet tall at the shoulder on four legs and weigh up to 660 pounds. When standing, they can reach up to 5.5 feet tall.
The second largest bear species in North America is the brown bear. Also known as the grizzly bear, they stand up to 4.25 feet tall on four legs and weigh 1,000 pounds. When standing, they can reach up to 8 feet tall.
The polar bear is the largest bear species and the largest terrestrial carnivore, standing up to 4.25 feet tall on four legs and weighing up to 1,000 pounds. When standing, they can reach up to 10 feet tall.
Bear Species | Height (Shoulder, Four Legs) | Weight (Approximate) | Height (Standing) |
---|---|---|---|
American Black Bear | Up to 3 feet | Up to 660 pounds | Up to 5.5 feet |
Brown Bear (Grizzly) | Up to 4.25 feet | Up to 1,000 pounds | Up to 8 feet |
Polar Bear | Up to 4.25 feet | Up to 1,000 pounds | Up to 10 feet |
Shoulder Hump
There are several differences that are easily noticed between brown bears and black bears at first glance. Brown bears have a pronounced hump at their shoulder, while black bears do not. The shoulder hump comprises a large muscle that black bears do not have.
- Shoulder Hump Size:
- Brown Bear (Grizzly Bear): Brown bears have a prominent shoulder hump. This hump is a large muscle mass above their shoulders, which gives them a distinctive, steep, and higher profile at the shoulder compared to their hindquarters.
- Black Bear: Black bears have a much smaller or almost non-existent shoulder hump. Their body profile appears more evenly rounded, with no significant hump above the shoulders.
- Shape and Purpose of the Hump:
- Brown Bear (Grizzly Bear): The shoulder hump of a brown bear is primarily made up of muscle and is especially well-developed in adult males. It serves as a powerful muscle for digging and digging for roots, rodents, and other food sources.
- Black Bear: Black bears have a less pronounced shoulder hump because their musculature is not as specialized for digging as that of brown bears. They rely more on their sharp claws for digging.
You can see the difference in the two pictures below.
Face
There are a few differences between the black bear’s and the grizzly bear’s faces and heads. Brown bears have concave, dish-shaped faces with small, round ears and a prominent snout.
Black bears have more prominent, large, pointed ears. Their face is not dish-shaped like brown bears but has a straighter profile.
Brown Bear (Grizzly Bear) Face:
- Muzzle Profile: Brown bears tend to have a more concave or dished facial profile, especially in adult males. This means their snout or muzzle has a noticeable dip or curve.
- Ears: Brown bears typically have smaller, more rounded ears relative to their head size. The ears are not as prominent or pointed as those of black bears.
- Facial Size: The overall size of a brown bear’s face, especially in adult males, is often larger and more massive compared to a black bear’s face.
- Eye Ridge: Brown bears often have a pronounced, somewhat bony ridge above their eyes, giving them a somewhat “crowned” appearance.
Black Bear Face:
- Muzzle Profile: Black bears tend to have a straight or slightly convex facial profile, meaning their snout or muzzle appears less dished than that of brown bears.
- Ears: Black bears typically have larger, more pointed ears relative to their head size. These ears can appear quite prominent, especially in some individuals.
- Facial Size: The overall size of a black bear’s face is generally smaller and less massive compared to a brown bear’s face, especially in adult males.
- Eye Ridge: Black bears usually lack the pronounced bony ridge above their eyes that is often seen in brown bears.
Polar Bear Face:
- Nose and Snout: Polar bears have a long and powerful snout (muzzle). This elongated snout helps them breathe more efficiently when swimming in cold water and allows them to detect scents from a distance, particularly the scent of seals, which are their primary prey.
- Large Black Nose: Polar bears have a large, black nose. This dark coloration is thought to help absorb and retain heat from the sun, which is important for thermoregulation in the extreme cold of the Arctic.
- Small, Round Eyes: Their eyes are relatively small and round, which reduces heat loss and helps protect them from the harsh Arctic winds and icy conditions.
- Small Ears: Polar bears have relatively small, rounded ears. These ears are also adapted to minimize heat loss and exposure to extreme cold.
Colors
It would be easy to believe that a black bear is black and a brown bear is brown. However, this is not the case. Black bears can be brown, and brown bears can be black. Both species can also be many other colors, from cinnamon to almost white.
Brown Bears (Grizzly Bears):
- Brown to Dark Brown: Brown bears often have brown to dark brown fur, which can range from light to very dark shades. Some individuals may appear almost black, particularly in coastal regions.
- Blonde or Light Phase: In some areas, brown bears can have a blond or light phase, where their fur is a pale, creamy color. These bears are sometimes referred to as “blond grizzlies.”
- Silver-Tipped: Some brown bears, particularly older individuals, may have silver-tipped fur on their backs, giving them a “grizzled” appearance.
Black Bears:
- Black to Brown: Despite their name, black bears can come in various colors. While many are black, they can also have fur that ranges from brown to cinnamon and even shades of gray.
- White Chest Patch: Black bears often have a distinctive white or light-colored patch on their chest, which can be helpful for identification.
- Bluish Sheen: In some lighting conditions, black bear fur may appear to have a bluish or violet sheen.
Polar Bear:
- Pure White: Adult polar bears typically have pure white fur, which helps them blend in with the snowy landscapes of the Arctic.
- Yellowish Stain: While their fur is mostly white, it can appear slightly yellowish or stained due to environmental factors like algae growth. This yellowing is more noticeable on the fur around their neck and head, which can take on a creamy or yellowish hue.
- Translucent Fur: Interestingly, polar bear fur is not actually white; it’s translucent. The white appearance is a result of light scattering through the clear, hollow, and reflective hairs, which also provide insulation and camouflage.
- Black Skin: Despite their white fur, polar bears have black skin. This adaptation helps them absorb and retain heat from the sun, assisting with thermoregulation in their frigid habitat.
Do Bears Have Whiskers?
All mammals (except monotremes) have whiskers, and bears are no exception. A bear’s whiskers do not give the same sensory function as most mammals. The hairs on a black bear do not provide sensory information to the bear’s brain. While some mammals use their whiskers to sense prey and find their way around, a bear’s whiskers do not function the same.
Sensory whiskers are called vibrissae due to the vibrations through the whiskers. Black bears have hairs around the snout but do not function as vibrissae. Brown bears also have hairs around their nose, but these are short.
As with other bear species, polar bears also have hair around the snout but do not have a set of sensory whiskers. Due to the size of all three bears, the function of the vibrissae is not needed, as they are in smaller, prey-driven animals.
Do Bears Have Tails?
Black bears, brown bears, and polar bears all have tails. The tails of all three bears are small, but only the brown bear still uses theirs. Brown bears use their tails to wipe secretions from their anal glands onto logs, trees, and other surfaces to spread their scent.
Bears have vestigial tails. Their tails are not used for the same purposes that most mammals do. Tails are generally used for balance, as in kangaroos and dogs, or to propel themselves forward while swimming. Bears do not need tails for either of these reasons, and they have been lost through evolution.
If you want to know more about why bears have tails, I have written this article.
Do Bears Have Belly Buttons?
Bears are mammals and are born with an umbilical cord. When the umbilical cord is released after birth, there is a small scar, as there is with humans. However, this soon fades and gets covered with fur. The belly button can be seen on all newborn bears, including black bears, brown bears, and polar bears.
Do Bears Have Good Eyesight?
Bears do have good eyesight, which is comparable to our own. There is a myth about bears that they have bad eyesight, but this is because bears have such an incredible sense of smell that they do not rely on their vision.
Bears move their eyes, so they do not have to move their head as much to see different directions. Bears have a horizontal field of view of 120 degrees compared to our field of vision of 135 degrees.
Bear eyes are similar and they have retinas like our own. They can focus on a specific area, but the size is small. The pupil of a bear is shaped like a slit but opens almost twice the width of our own, helping them see in low-light conditions.
Bears see in color, not black and white. Bears have ten times the amount of rods in their eyes as us, which helps collect light, allowing them to see well in the dark. Light reflects from the back of the retina, called the tapetum lucid, effectively doubling the amount of light the bear sees.
Do Bears Have Paws?
Bears have paws at the end of their legs. However, the feet are not the same size on the front and back. In the front, the claws are shorter than the paws on the back of the bear.
The paws on the front are used more than the paws on the back. The claws on the front help the bear rip into logs and tree trunks that may have food and insects.
The evolution of bears is fascinating. Find out more here
Do Bears Have Thumbs?
Although they have the same joints as human hands, bears do not have thumbs. The joint is hinged, allowing the toes to curl towards the pad of the paw. Black bears are good climbers, but not because of the shape of their paws.
Their excellent climbing abilities are due to their claws, which allow them to clasp onto trees and even climb up the side of mountains.
Brown grizzly bears cannot climb trees, as their claws are not powerful enough to grip the bark, and adults are too heavy to support themselves. Polar bears also cannot climb trees due to their extreme weight.
Want to know how fast bears climb trees? It may surprise you
Do Bears Have Retractable Claws?
Black bears, brown bears, and polar bears all have fixed claws. Their claws do not retract as lions would. A bear track will always show the feet on the end of the paws.
While the length and shape of bear claws can vary between species and individuals, they are not designed to retract into the paw like the claws of a cat. Bears use their claws for a variety of tasks, but they cannot retract them like a cat’s claws can.
Do Bears Have Legs Or Arms?
Bears have both legs and arms. They are classified as mammals and belong to the order Carnivora, which includes various carnivorous mammals. Bears are known as “quadrupeds,” which means they typically walk on all four limbs. Their front limbs are often referred to as “arms” or “forelimbs,” and their hind limbs as “legs” or “hind limbs.”
Do Bears Have Knees?
Like most mammals, bears have jointed legs that include a knee joint. The knee joint is found in the hind limbs of bears and is essential for their ability to walk, run, and perform various movements. The knee joint allows for flexion and extension of the leg, enabling bears to move their hind legs in a way that is necessary for their mobility and locomotion. Just like humans and many other mammals, bears rely on their knee joints to support their body weight and engage in various activities.
Do Bears Have Elbows?
Elbows are found in the front limbs (forelimbs) of bears, just like in most mammals. These joints play a crucial role in the movement and flexibility of a bear’s front legs. The elbow joint allows for bending and extending of the forelimbs, which enables bears to perform a variety of actions, including walking, running, climbing, digging, and manipulating objects. The presence of elbows in bears is essential for their overall mobility and their ability to perform various tasks in their daily lives.
In a more precise zoological context, the forelimb joint of a bear, while functionally similar to an elbow, may not be referred to as an “elbow” in the same way we refer to the human elbow. Similarly, the joint in the hind limb may not be referred to as a “knee” in the same way we refer to the human knee.
How Many Fingers Or Toes Does A Bear Have?
Bears typically have five digits on each of their front paws and five digits (toes) on each of their hind paws. These digits are equipped with claws, which are used for various purposes such as grasping, climbing, digging, and catching prey. While the number of digits remains relatively consistent, the size and shape of claws can vary between bear species and individuals.
Tracks
There are notable differences in the tracks between the three species of bears in North America. Both black and grizzly bears show their claws in their ways, whereas polar bears do not.
Distinguishing between black bear and brown bear tracks can be challenging, as the tracks of both species can have some similarities. However, there are some general differences you can look for:
- Size: Brown bear tracks are usually larger than black bear tracks. Grizzly bears, a subspecies of brown bear, can have particularly large tracks. Black bear tracks are typically smaller and more compact.
- Claw Length: One key difference is claw length. In brown bear tracks, you often see long, curved claws that extend beyond the toe pads. In contrast, black bear claws are shorter and less curved, usually not extending far beyond the toe pads. This difference is more noticeable in soft ground where claw marks are more evident.
- Shape: Brown bear tracks are often more rounded in shape, while black bear tracks can be more oval or have a more triangular appearance.
- Toe Arrangement: In brown bear tracks, the toes are often more evenly spaced and can appear somewhat symmetrical. Black bear tracks may show more variation in toe spacing and less symmetry.
- Toe Count: Both black bears and brown bears typically have five toes on each paw. However, brown bear tracks may sometimes show fewer than five toes due to variations in how the claws register in the track.
- Track Depth: Brown bears tend to make deeper tracks on soft ground due to their larger size and weight.
Do you know if bears can swim? Find out here
References and Further Reading
NHPBS – Brown bear
San Diego Zoo – Bears
Science Direct – Polar bears
ESA Journals – Den-site characteristics and selection by brown bears
Bears: Without Fear by Kevin Van Tighem
This book offers insights into the natural history and behavior of bears, including their physical characteristics and adaptations.
Bears of the World by Lance Craighead and Mollie Craighead
This comprehensive guide explores all eight bear species found worldwide, discussing their physical characteristics, behavior, and conservation status.
Bear: Spirit of the Wild by Paul Nicklen
While primarily a visual book with stunning photography, it also includes information about bear biology and characteristics.
The Hidden Life of the American Black Bear by Michael C. Main
This book delves into the biology and behavior of the American black bear, covering topics such as anatomy, physiology, and ecology.
Bears of North America by Lynn Rogers and Sue Mansfield
Focused on North American bears, this book provides detailed information about their physical traits, behavior, and ecology.
Bryan Harding is a member of the American Society of Mammalogists and a member of the American Birding Association. Bryan is especially fond of mammals and has studied and worked with them around the world. Bryan serves as owner, writer, and publisher of North American Nature.