Sometimes Bill Stiver, a wildlife biologist in the Great Smoky Mountains National Park, feels more like a social scientist than animal expert — especially when it comes to bears and tourists.

In the natural world there are certain experiences that rivet our attention and remain stored in our memory banks. Through the years I’ve written about my own encounters with rare plants, endangered landscapes, copperheads and timber rattlers, coyotes, skunks, eagles, red and gray foxes, box and snapping turtles, and so on. Not infrequently, I’ve received feedback from readers reporting that they have had similar experiences.

Managers at Great Smoky Mountains National Park are bracing for a higher-than-normal level of bear activity this fall and are warning Park visitors and neighbors to be especially careful about protecting their food and garbage from bears.