When it comes to some U.S. state mammals, the risk of extinction is practically non-existent. The official state mammal of Arkansas, Illinois, Michigan, Mississippi, Nebraska, New Hampshire, Ohio, Pennsylvania, and South Carolina, for example, is the common white-tailed deer which is about as much at risk for extinction as house sparrows and brown rats. If the white-tailed deer ever goes extinct, we’ll probably have preceded it.

California, on the other hand, has a state mammal that has been extinct for almost a century now. California’s state mammal is the California grizzly bear (the same bear seen on the state flag) and was a wide-ranging bear found throughout the state. Found, that is, until the California gold rush started to put a serious hurt on the bear population. Starting around 1848, gold miners, bounty hunters, and settlers hunted the bears because of the danger they presented to humans and livestock, and for their meat and fur, reducing them to a fraction of their previous population. By the early 20th century, there were very few left, and the last time a California grizzly was hunted or even spotted was in the early 1920s.

More Info: en.wikipedia.org