Bears are highly adaptable animals, and their diet reflects this flexibility. If you have ever wondered, “Do bears eat squirrels?”, the answer is yes, but it is rarely the result of a dedicated hunting effort. Bears are classified as opportunistic omnivores, meaning they consume a diverse range of plant and animal matter depending on what is most readily available. This feeding strategy allows them to survive across varied habitats and changing seasons, maximizing caloric intake with the lowest possible energy expenditure.
The Omnivorous Nature of Bears
The typical bear diet is much less carnivorous than many people assume, being largely composed of vegetation and invertebrates. The majority of a bear’s caloric intake comes from plant sources such as berries, nuts, roots, and grasses, which they graze on extensively throughout the warmer months. For example, brown bears often derive up to 90% of their diet from plant matter, despite their powerful build. Bears also routinely consume insects, particularly grubs and ants, which provide a concentrated source of protein and fat necessary for preparing for hibernation.
Bears constantly shift their dietary focus based on seasonal food availability. In the spring, they may rely more on carrion or the new growth of grasses. Late summer and fall are dedicated to hyperphagia, a period of intense eating focused on high-calorie foods like berries and acorns. Their digestive systems are built for this generalist approach, allowing them to extract nutrients from a wide variety of food items. This adaptability makes them successful in diverse ecosystems across North America and Eurasia.
Squirrels: An Opportunistic Meal
When a bear consumes a squirrel, it is typically an incidental catch rather than the result of a planned hunt. Tree squirrels are fast-moving, arboreal animals that are difficult and energetically costly for a large bear to pursue. The small amount of meat and fat a squirrel provides does not justify the energy needed for a focused chase, so bears are much more likely to target ground squirrels or other burrowing rodents.
The consumption of tree squirrels often happens when a bear is investigating a tree or log for another purpose. A bear might be trying to access a cache of nuts, a bee hive for honey and larvae, or searching for a den site when it accidentally encounters a squirrel or its nest. In these scenarios, the squirrel becomes an easy, high-protein bonus to a meal the bear was already committed to finding.
Species Differences in Small Mammal Consumption
The likelihood of a bear consuming a small mammal like a squirrel differs notably between species, driven largely by physical characteristics and habitat preference. American Black Bears are excellent climbers, possessing shorter, curved claws that allow them to ascend trees easily. This climbing ability increases their probability of encountering tree squirrels or raiding their nests, making them more prone to incidental consumption of arboreal rodents.
In contrast, Brown Bears, which include Grizzlies, are less adept at climbing mature trees but are formidable diggers. They possess long, straight claws and a distinct shoulder hump powered by muscle, which are adaptations for excavating the earth. This specialization makes them highly effective at digging up burrowing animals like ground squirrels and pocket gophers, which are a regular, albeit small, source of protein in their diet. Grizzly bears also often prioritize larger sources of protein, such as salmon or ungulate calves, making a small tree squirrel a comparatively minor dietary component.