From my vantage point in North America, it’s easy to think about bears and focus on the three species that share this landmass. However, bears are actually a larger group, with eight extant (or living) species and more than 100 extinct species documented by fossil record. Spread across varied ecosystems and four continents, bears have a diverse family tree that is worth exploring. 

But first, let’s talk about taxonomy, the scientific practice of classifying species according to their similarities. These classifications may be more familiar than you expect. If you remember the standard ‘Kingdom-Phylum-Class-Order-Family-Genus-Species’ system from biology class, you already know the basics. 

The classification of bears is relatively straightforward compared to other groups. They are animals with spinal cords and fur, which lands them in the Animal kingdom, Cordate phylum, and Mammal class. Skull and tooth characteristics place bears in the Carnivore order (regardless of diet), along with everything from tigers to seals. Depending on your reference, there are approximately 12 families of carnivores, including the bear family (Ursidae). Ursids are divided into five genera that reflect their relatedness, and finally, each species has a name or specific epithet. Because common names for wildlife are not consistent across cultures and languages, scientists use the genus and specific epithet together to identify species and avoid confusion; this is called the Latin or scientific name. Think of it like a first and last name for every species—for example, the American black bear is Ursus americanus. 

The most distinctive bear species is undoubtedly the giant panda (Ailuropoda melanoleuca). It’s also something of an outlier. Historically, there was debate about whether giant pandas are true bears or more closely related to raccoons. The current consensus seems to be that giant pandas are bears, but may not be as closely related as the other species. Giant pandas have a distinct black and white coat and are similar in size to American black bears. Despite being classified as carnivores, their diet consists almost exclusively of bamboo. Historically, giant pandas occurred over a large portion of southeast China, but habitat destruction has severely restricted the species to a few small, mountainous areas. The International Union for Conservation of Nature (IUCN) estimates that there are between 500-1000 mature individuals worldwide and, despite low reproductive rates, modest population increases have allowed giant pandas to improve their classification from endangered to vulnerable. 

The Andean bear (Tremarctos ornatus) is the only living ursid species native to South America. They are similar in size to the American black bear. They have black coats with distinct white or tan circles around their eyes and light patches extending over their muzzle and throat. Andean bears live in tropical, northern portions of the Andes Mountains and feed primarily on plants and fruit, but they will consume prey species given the opportunity. They spend extended periods of time living in trees and build “platforms” where they feed and rest. IUCN population estimates range from 2,500-10,000 individuals with a downward trend due to habitat loss and poaching. Andean bears are classified as vulnerable to extinction. 

Sloth bears (Melursus ursinus) are a slightly larger species (200-300 lbs). Their black coats are long and shaggy with a prominent V-shaped chest blaze. They have long claws and modified noses that help them dig and suck up insects like a vacuum cleaner; their diet largely consists of ants, termites, and fruit. Sloth bears occur throughout portions of India, Bangladesh, and Sri Lanka. IUCN lists them as vulnerable with decreasing population trends, but there are notably few reliable population estimates. Major threats to this species are considered habitat loss and human conflict. 

Just east of the sloth bear range and throughout much of southeast Asia resides another ursid, the diminutive sun bear (Helarctos malayanus). Considered the smallest species (55-150 lbs), sun bears have a short, black coat, light muzzle, and pronounced chest blaze. They occupy tropical and sub-tropical forests and, like Andean bears, spend a lot of time in the trees. They have a broad diet of insects, fruit, and small prey. Major threats to their conservation include deforestation and poaching for commercial markets. IUCN classifies sun bears as vulnerable with decreasing population trends, but again, better population estimates are needed. 

Asiatic black bears (Ursus thibetanus) are similar in size to their American counterparts. They have a medium-length black coat with a shaggy neckline, a large chest blaze, and a light-colored soul patch on their lower jaw. They subsist mostly on plants along with some insects and small prey. Historically, Asiatic black bears occupied an expansive range from the Middle East, across the Himalayas, and throughout much of Asia. The species overlaps in some areas with sloth bears, sun bears, and brown bears (Ursus arctos); unsurprisingly, they face many of the same conservation challenges. Globally, IUCN considers Asiatic black bears vulnerable with decreasing populations, but it can be especially difficult to gather population estimates for species that range over multiple countries with differing wildlife policies. 

Among ursid species, American black bears have the most variable appearance. On average, they are medium-sized (150-250 lbs) but can range from less than 90 lbs to more than 600 lbs. Their coats vary from blonde to black, and chest blazes are common but not uniform. American black bears are highly adaptable to a wide range of ecosystems. IUCN population estimates approach a million animals with upward trends, and American black bears are classified as a species of least concern. That’s not to say they are unimportant; IUCN works to gauge a species’ risk of extinction, not conservation value. This is the ideal category for a species managed through sustainable harvest practices. 

Brown bears once roamed across most of the Northern Hemisphere and still occur in large portions of North America, Asia, and Europe. They have the largest geographic distribution of any bear species, and across their range numerous brown bear subspecies are recognized, including the infamous grizzly—but that is a topic for another day. Most brown bears are indeed some form of brown, but coat colors vary from light to dark. Brown bears are a large species (200-1000 lbs) and adults do not readily climb trees. Their diets consist of plants, fruits, insects, and prey, including large mammals. IUCN population estimates for brown bears are around 110,000 individuals with stable population trends. They are classified as a species of least concern, and several countries allow carefully managed harvest. 

Last but not least, the polar bear (Ursus maritimus) is the largest ursid species on the planet. This solid white bear is highly aquatic and occurs throughout the arctic region. They are the only fully carnivorous bear species, consuming almost exclusively seals and other marine mammals. IUCN considers polar bears vulnerable with potentially declining trends, but good population estimates are not available. The most significant threats to this species are changing Arctic conditions and reduced sea ice, which polar bears require to move and hunt. 

As I read about these amazing species and the challenges they face, I am grateful for the many conservationists who work to recover, conserve, and sustainably manage each of them. But I’m also reminded not to take my local wildlife resources for granted. I hope you feel the same.