Monday, November 7, 2011

Animal of the Week: Grizzly Bear

The grizzly bear is a subspecies of brown bear that generally lives in the uplands of western North America. It is thought to have descended from the Ussuri brown bear that crossed from the Russia to Alaska about 100,000 years ago. The word grizzly refers to their grey hairs within their fur that give them a grizzled look. However in 1815, American naturalist George Ord, mistook this for the word "grisly" and gave the animal the Latin biological name of Ursus arctos horribilis.

Although grizzlies are within the order of Carnivora and have the digestive system of a carnivore their diet is that of an omnivore. Their main prey includes moose, deer, sheep, elk, bison, caribou and even black bears. In coastal areas they will also eat salmon, trout and bass. This higher protein diet tends to make them larger than inland grizzlies. Other parts of their diet are made up of tubers, berries, nuts and grasses. In some areas they will also eat landbugs, ants and bees.

Grizzlies' strongest sense is smell. Some scientists believe grizzlies can smell something up to 29 kilometers (18 miles) away. This can lead to them pursuing carrion or catches of other animals.
An interesting battle for food has been commonly observed between grizzlies and grey wolves. Often a grizzly will sniff out when a pack of grey wolves has caught something like an elk. The grizzly will try and take over the carcus but not without a good flight from the wolves. The wolves will use tactics such as one wolf distracting the grizzly while the others feed. Sometimes the grizzly will come under attck from several wolves. The attack is normally in the form of a few nips from the wolves in the hind legs. To combat this the grizzly will simply sit down and defend itself from all directions.

Gizzlies play a vital role in the ecosystems within which they live. Apart from being an apex predator they also aid germination of some plants. When eating whole fruits they will later excrete the seeds were they have been observed to successfully grow. Spruce trees near salmon populated rivers have also been found to be richer in nitrogen, due to salmon carcasses being carried into the forests by the grizzlies. This acts as a form of fertilizer. Grizzlies foraging also helps to airate soil.

A common myth is that grizzlies, as well as other bears, hybernate. This is not actually true, rather they go into a state of dormancy. In true hibernation, an animals body temperature drops to a few degrees above freezing and if disturbed it takes a couple of hours to wake up. Although grizzlies temperature is somewhat lower than normal, it isn't as low as true hibernators. During winter sleep, bears are alert and easily aroused. True hibernators such as ground squirrels, marmots, etc rouse themselves several times during the winter to eliminate body wastes. Bears, on the other hand, do not urinate or defecate during their winter sleep.They will genrally, settle in to their often self-dug dens after the first serious snowfall as it is then safer from other predators. Females will give birth during this time. They generally give birth to between one and four cubs, every three years. At birth, the cubs will weigh about 500g and will survive by cuddling up to their mother and drinking her milk. Their life span in the wild is between 15 and 18 years, in captivity 28-32 years.

Grizzlies used to exist all the way down to Mexico but their range has reduce over the years due to human actions. One popular place for seeing them is within Yellowstone National Park. Unfortunately just 600 grizzly bears remaining in Greater Yellowstone and now the federal government is challenging the Greater Yellowstone Coalition's 2009 court victory that put the bears back on the Endangered Species list. Although numbers have increased in recent years, many believe that it is too early to relax the conservation of these magnificent animals. With continued pressure of further development there is a risk that grizzly habitat may become diminished.

Can you imagine travelling to Yellowstone and knowing that there are no grizzly's left. Click here to sign the petition requesting that Secretary of the Interior Ken Salazar keep grizzly bears on the Endangered List and thus ensuring they are still around for your next visit to the park!                                    

Bear Medicine
In many traditions the bear symbolises healing. To the Ainu people of the northern islands of Japan, the bear was a mountain God. Among Finno-Ugric people the bear was God of Heaven. In India, bears are believed to prevent sickness.

The bear is also known for it's dormancy in winter. It retreats to the dark cave or den to be by itself. This is part of the bear's survival adaptations, giving them strength for the next cycle's warm weather. Resting in winter can help you to be prepared and strong for the next Spring.

If bear has come before you it may be time for you to retreat to your inner cave for a while. Go inward, reflect, rest and relax and heal yourself from the inside out.

No comments: