Black bears have a varied diet that includes many types of food. In this article, I look at what makes up the diet of a black bear.
Black bears eat a variety of foods to supplement their dietary requirements. 90% of their diet comprises plants, but they also eat mammals, fruits, nuts, berries, fish, insects, birds, eggs, reptiles, and amphibians.
There are three bear species in North America, the American black bear, the brown bear, and the polar bear. Here I discuss the diet of the American black bear.
What Do Black Bears Eat?
Black bears are considered carnivores but have a varied diet, including caribou, deer, elk, moose, and plants and fruits.
Black bears will also eat fish, birds, and eggs. They also eat various types of insects, including bees and wasps.
American black bears can spend up to seven months hibernating every year. To survive during the winter, they must ensure that they build their fat reserves. Without these fat reserves, it would be impossible to make it through the winter.
Black bears have a huge appetite when not hibernating in the warmer months. During these months, they spend almost all their time eating, traveling, and sleeping. Due to the long hibernation period, black bears prefer foods high in fat, sugar, and protein.
Which Plants Do Black Bears Eat?
Plants, including alfalfa, clover, and dandelions, are broad-leafed and soft for the bears to digest. Flowers and roots are eaten in large quantities, although they do not like to expend energy digging for roots.
Bears eat flowering plants such as Lillies and fireweed during the summer to supplement their nutrition.
Plants are essential for nutrients when the black bear wakes up from hibernation. Coinciding with the end of hibernation, new shoots and plants begin to grow in the spring after the long winter.
These new plants are soft and easy to digest for the re-emerging bear. After hibernation, a black bear’s stomach takes a few weeks to start working correctly again.
Although black bears supplement their diet with meat, up to 90% of what they eat is plant material. Whereas ungulates such as cows, elk, and whitetail deer have specialized stomachs that can efficiently break down plant matter, the black bear does not.
Ungulates have a long digestive tract consisting of four sections in the stomach. Each team has a different function, with specialized bacteria that help break the material down.
Black bears only have a one-chambered stomach. Although it is not as functional when breaking down the plant material, their digestive tract is very long.
The long digestive tract allows black bears to pull extra nutrition from plants. Black bears will eat plants when they are the most nutritious and tender.
Which Mammals Do Black Bears Eat?
Black bears are carnivores and will eat young caribou, deer, elk, and moose. Many ungulates will give birth in the same place every year, and black bears will remember where deer and elk have given birth, deliberately hunting in those areas every year. In other locations, the bears will come across the young while traveling.
Black bears can take down large hoofed mammals such as caribou, moose, or elk but generally only do so if weakened or injured. A black bear does not want to risk injury to itself before hibernation. The number of young animals eaten by black bears can be significant in some areas.
The geographic location and the habitat play a large part in which animals black bears will eat. Black bears feed primarily on larger animals for increased protein in some polar areas. In colder areas like Northern Labrador, the black bears will take down fully grown caribou, deer, and moose.
Black bears eat other animals, including beavers, bobcats, coyotes, ground squirrels, mice, red foxes, and wolves. Black bears will also feed on carrion left behind by other species, chasing other animals away from a kill.
Black bears may dig small mammals, such as gophers, from their burrows in spring. However, there are usually much larger animals that are easier to find and don’t take up as much energy.
Black bears may also find an abundance of animals that have not fared well during the long, cold winter. Old or weakened animals such as caribou, deer, elk, and moose that have died during the freezing season are left for the bears to feed on in spring.
The protein-rich carcasses can help a bear that has woken up from hibernation throughout the winter.
Which Berries and Fruit Do Black Bears Eat?
Black bears also eat berries and fruits, which are essential for nutrition and energy. Fruit eaten by bears includes apples, blackberries, cherries, elderberries, huckleberries, plums, raspberries, and rose hips.
Raspberries and other blackberries become ripe early in the year, allowing the bear to eat them before moving to other fruit that ripens later. Black bears can decimate a farmer’s crop of berries, with some eating more than 30,000 a year.
Black bears also eat various nuts, and they will peel these from the cones of deciduous and evergreen trees. Hazelnuts are one of the favorite nuts for a bear, with some bears traveling considerable distances to reach a harvest.
Which Insects Do Black Bears Eat?
Black bears eat an extensive range of insects and worms. These include ants, grubs, grasshoppers, beetle larvae, moths, caterpillars, and earthworms. Black bears have a sticky tongue that is used to catch insects.
Ants are an essential food source for bears as they are high in protein. When fruit and berries are hard to find, ants are eaten in significant quantities. Black bears eat ants and are young in the pupal and larval stages.
Bears will also feed on bees and wasps—bears like honey and the bees and larvae found in beehives.
In the Sonoran desert in Arizona, Apache cicada nymphs were the dominant insect eaten, making up most of the scat.
Do Black Bears Eat Birds and Eggs?
Black bears will eat various birds, including ducks, geese, and grouse. As birds can be challenging to catch, they will also feed on bird eggs.
Black bears are excellent at climbing, and black bears can find eggs in nests out of the reach of most predators. The newly hatched birds are too young to escape, so they make an easy meal.
However, they generally take most of the eggs and young chicks from the nests of ground-nesting birds.
Which Reptiles and Amphibians Do Black Bears Eat?
Bears may also feed on alligators in the south in Louisiana and Florida. Because alligators can be formidable opponents, bears do not want to risk injury from a full-grown adult, so that they will raid alligator nests for eggs and the newly-hatched young.
Black bears also eat other reptiles and amphibians, including frogs and lizards, although these make up a small portion of their diet.
Which Fish Do Black Bears Eat?
American black bears will also feed on various types of fish, with species depending on their location. Black bears along the Western Pacific Coast feed on the supply of salmon spawning in the area, which makes up a large part of their diet.
Other fish include trout, which swim further inland in streams. Hungry black bears can easily catch shallow-water fish with their claws and mouths, with carp and catfish making up a significant portion.
What Do Black Bears Eat In The Winter?
During the long winter months, black bears that are not hibernating can be found in search of food. Black bears are primarily herbivorous and thus rely mainly on plants for nourishment, like winter-dormant grasses, buds, twigs, and fruits.
When these are hard to find, black bears switch to carrion to keep themselves fed. Black bears are scavengers that sometimes go out of their way to search for wounded or sick animals nearby to increase their chances of a meal.
Do Black Bears Practice Cannibalism
Black bears have also been seen to indulge in cannibalism, eating young black bears and adult female bears in some areas. Large adult males mainly carry out cannibalism between black bears.
References and Further Reading
NCBI – Cicada nymphs dominate the American black bear diet in a desert riparian area
Sciencedirect – Evaluation of black bear diet
Journal of Mammalogy – Food availability and foraging near human developments by black bears