Don't worry, the series is still going. Slowly but surely.

The Brown Bear (Ursus arctos) is the most widely-distributed of all bear species, if not the most numerous (that title goes to the Black Bear). They can be found in much of Asia, North America, Europe, and the Atlas Mountains of northern Africa (none spotted recently, unfortunately), though their numbers are dwindling in some of those areas, and they have been completely extirpated from parts of their historical range. There's no firm consensus on how Brown Bears are classified, since there are a variety of ways to group them. Some classifications have proposed as many as 90 subspecies, while recent genetic testing could narrow it down to as few as five clades. In North America, the Brown Bear is known as the Grizzly Bear.

The size of adult Brown Bears is incredibly varied, being dependent on factors such as age, sex, range, time of year, and individual circumstances. The larger subspecies, the Kodiak and Ussuri Bears of North America and Asia, respectively, rival the polar bear in size. In general, the bears will weigh the least in the spring when they emerge from hibernation, and weigh the most in the late fall, as they're building up fat stores for the winter. Their general measurements are presented in ranges:

  • Body length: 4.6 to 9.2 feet (1.4 to 2.8 meters)
  • Shoulder height (when on all fours): 28 to 60 inches (0.7 to 1.5 meters)
  • Weight: 220 to 1,400 pounds (100 to 635 kg)


There is huge variety in the diet of Brown Bears, who are considered to be some of the most omnivorous animals on the planet. The specifics vary based on what is available in any given part of their range, but it kind of seems like they can and will eat anything just in case it happens to be food. Ninety percent of their food intake is vegetation, consisting of grasses, berries, seeds, nuts, fungi, and roots. They will also eat insects and their larvae, clams, crabs, fish, birds, eggs, small mammals, and large mammals like ungulates and bovids. They are also not averse to eating food intended for humans, and will scavenge trash cans to get at it. If a bear becomes too accustomed to human food and starts to lose its wariness of humans, things get dangerous. This is why it's incredibly important to never feed wild animals.

The mating season of Brown Bears occurs between May and July. Bears will form serially monogamous mating pairs, which means that a male and female bear will mate only with each other during one season, but may form new monogamous pairs the next. Implantation of the fertilized eggs is delayed for about six months, and the pregnancy usually starts active gestation during the winter. Females emerge in spring with one to four cubs, who will stay with their mother for two to four years. It's important for bear cubs to be protected when they are young, small and vulnerable, because male bears will kill cubs if they encounter them.


Brown Bears are more likely than Black Bears to attack humans, although in most circumstances they prefer to avoid humans when possible. In North America, Brown Bears are responsible for an average of two human fatalities each year. The most likely reasons a Brown Bear might attack a human are when the bear is surprised or startled by the human's presence, or if the bear is curious about the human. In many cases, fatal attacks are carried out by female bears attempting to protect their cubs. Brown Bears are considered to be a species of least concern by the IUCN.

Source for all images used in this post.