Only the black bear is known to exist in Rocky Mountain National Park. It's northern cousin, the grizzly bear, is no longer found in Colorado. Black bears make a point to avoid humans, so they are not often seen.
Black bears are large mammals that can be five to six feet long and weigh 200-600 pounds. They have stalky bodies with short, powerful legs that allow them to climb trees by gripping the trunk with claws on their paws. They are fast and can easily outrun a person. Despite the name, black bears are not always black in color. Their fur can also be dark brown, cinnamon colored or even lighter.
Black bears are solitary animals except for females (called sows) with cub families. They wander through home ranges of 10 to 250 square miles as snow recedes, plants sprout and berries open.
Mating season peaks in May and June, but egg implantation is delayed until the fall when the sow is ready to den up for the winter. This allows the female to conserve fat reserves and energy during the growing season. If she doesn't gain enough weight before hibernation, her body can reabsorb the eggs for her own survival.
Males can breed at three years of age, while females first have cubs around five years old. Females with cubs do not breed again until the cubs leave. Females give birth to litter sizes of one to five cubs every other year. Cubs are born in the mother's winter den after a two to three month gestation period. They are born toothless, with closed eyes and fine, soft fur. They may nurse throughout their first summer, and remain with their mother for up to a year and a half.
Bears are omnivorous, meaning they eat both plants and animals. About 90 percent of their main diet consists of roots, berries, nuts and insects. They can be active anytime, but most often during the morning and evening twilight. When not feeding, they rest in day beds next to logs in windfall trees, dense brush or in a depression. Black bears can live up to 30 years, but the average is 20 years.They are very opportunistic and can easily develop a taste for human food and garbage. Bears who become habituated to obtaining this kind of food are often killed.
If you see a black bear, stop and do not run. Stay calm and pick up small children. Make lots of noise, shouting and clapping your hands. Back away slowly. Stand tall, but if you are attacked, fight back.
Black bears will eat almost anything. Most conflicts between bears and people are linked to careless handling of food or garbage. Once a bear has found food which is easily accessible, it will overcome its wariness of people and visit the site often.
If you are on the trail, keep food with you at all times and do not leave your pack unattended. At backcountry campsites, all food, cooking equipment, garbage and other scented items must be stored in a carry-in/carry-out bear-resistant food storage canister. This is required from April 1 to October 31 at all backcountry sites below treeline.
In campgrounds, all scented items as well as water containers and pet food must be stored in a closed vehicle or storage locker provided at the campground. Storage in tents, pop-up campers, sleeping bags or under tarps is prohibited. If left unattended, these items are subject to confiscation by park rangers. The only exception to these rules occur during food transport, preparation, eating and clean-up.