Life Cycle Young born bears are vulnerable, being blind, naked and weighing only g. Cubs grow quickly, reaching 25kg by 6 months, and continue lactating for 18 to 30 months while eating a variety of foods. Cubs usually remain with the mother until the third or fourth year of their life.
Although they mature sexually between years of age, the species continues to grow until years old. In the wild, the brown bears can reach 20 to 30 years of age. Despite this long life expectancy, most brown bears die very early. Breeding Brown bears mate from May to July, and a gestation of to days follows, with births occurring from January to March, usually while the female is still in hibernation.
She generally lays down two to three offspring, and breeds again 2 to 4 years later. Diet Brown bears are omnivorous, and their diet varies with the season - from grass and shoots in the spring to berries and apples in the summer, nuts and plums in autumn.
All year round they eat roots, insects, mammals including moose and elk in the Canadian Rockies , reptiles, and of course, honey. In Alaska, grizzlies feed on salmon during the summer. Population and Distribution The total global population of brown bears is estimated to be above ,, Russia has the largest number of brown bears, believed to be over , The species is still fairly common in the mountainous regions of western Canada and Alaska, where its population may reach 30, individuals.
In other parts of the United States, fewer than 1, grizzly bears remain. Historical Distribution The brown bear was once distributed in northern and central Europe, Asia, the Atlas mountains of Morocco and Algeria northern Africa , and western North America as far south as Mexico.
The populations of the Sierra Nevada and southern Rockies have been extirpated, while those of Northern Mexico were lost in the s. Grizzly numbers were estimated at , in the United States in the early s. What are the main threats? Bear gall bladders reportedly bring high prices on the Asian aphrodisiac market, but although demand is growing, there is no evidence that products derived from bear parts have medical value.
The bears have succeeded immensely, and are surprisingly easy to train. On the other hand, the Yellowstone National Park has also given an immense help to the recovery of the Grizzly Bear. The video linked below shows how the population of the National Park had increased and why. People never thought that the population of the grizzly bear could ever recover due to its huge needs concerning the environment and its surroundings. But it is astonishing how the population grew thanks to monitoring the species.
It is now common for tourists to see more than 1 bear in the park every time they come to visit, in comparison to before where the bear sightings were way more scarce. In , there were around bears living in this park, however, after human intervention to save the species, there are now more than bears in the Yellowstone conservation Park. Therefore we have made a remarkable change and increase in the population. United States.
National Park Service. But the biggest threat to the grizzly is human-caused mortality. Grizzlies become habituated to humans because of what biologists call "attractants," which include garbage pet foods, livestock carcasses, and improper camping practices.
This can eventually lead to conflicts between people and bears - not only in populated areas of the grizzly's range but also in back-country recreation sites. Today, in the lower 48 states, grizzlies can be found in small portions of Wyoming , Montana , Idaho and Washington.
There are approximately grizzlies living in the northwestern Montana Rockies, about in or around Yellowstone National Park, about 10 in the Selkirk Mountains in northern Idaho and northeast Washington, another 15 or so in the Cabinet-Yaak ecosystem in northern Idaho and western Montana, and perhaps 10 or more in the North Cascades of upper Washington state. In Alaska , where they are called brown bears, they are estimated to number more than 30, There are also populations of grizzlies in Alberta and British Columbia.
One goal of the agency which manages grizzly bears, the U.
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