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Grissly Bear Management | Concepts | Grizzly Bear Management |
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DIMENSIONS:
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Conservation of the Yellowstone Grizzly- an uncertain future -
In the last century, increases in human development and population have drastically reduced the grizzly bear's (Ursus arctos horribilis) range and habitat. Today, the grizzly has been reduced to 1% of its former numbers in 1-2% of its former range (see range map below). Fragmented zones of existence are all that remain for the Grizzly Bear, with the continued destruction and degradation of grizzly bear habitat and human-caused mortality remaining the greatest threats to their existence. In the lower forty-eight states grizzly numbers have been estimated to be about 1,000--reduced from an estimated 50,000 to 100,000 before the West was settled.
Presently it’s thought that about 90 percent of Americas surviving grizzly bears exist in the Yellowstone and Northern Continental Divide ecosystems, and most experts believe that utmost caution should be taken with these last remaining populations representing the lower forty-eight states. In 1975, the grizzly was listed as "threatened" under the Endangered Species Act, and afforded federal protection. Since that time the grizzly has maintained a tenuous foothold in the Yellowstone region with long-term survival remaining uncertain. In addition to the threats from the loss and fragmentation of habitat and human caused mortality, concerns such as the loss of food sources and global warming are compounding problems effecting grizzly recovery. Recent scientific research states that grizzly bear numbers within the Yellowstone region have remained about the same and have changed little since the grizzly bear was listed as threatened (Matson and Pease, 1999). Others believe they are seeing more bears and that is a sign that grizzly numbers are increasing. In response, scientists say that if more bears are being seen it’s because the animal is looking outside wild areas of the park for food as habitat is now in worse shape than in 1975 when the population was listed. Furthermore, the rising sea of development surrounding Yellowstone, creating a problem for long-term viability has effectively cut off these animals from other grizzly populations for over 50 years. And since there is often a lag-time between destruction of habitat and when these effects appear as a decline in population size, habitat loss today could mean extinction in the future.
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