Grizzly bears are emerging from hibernation in the Greater Yellowstone Area and hikers, skiers and snowshoers are advised to stay in groups of three of more, make noise on the trail and carry bear spray.

Bears begin looking for food soon after they emerge from their dens and are attracted to elk and bison that have died during the winter. These carcasses are an important food source, and bears can react aggressively if surprised when feeding.

Yellowstone regulations require visitors to stay 100 yards from black and grizzly bears at all times. The best defense is to stay a safe distance from bears and use binoculars, a telescope or telephoto lens to get a closer look.

While firearms are allowed in the park, the discharge of a firearm is a violation of park regulations. Bear spray has proven to be a good last line of defense, if kept handy and used according to directions when a bear is within 30-60 feet.

Visitors are also reminded to keep food, garbage, barbecue grills and other attractants stored in hard-sided vehicles or bear-proof food storage boxes. Bear sightings should be reported to the nearest visitor center or ranger station as soon as possible.

Updated bear safety information is available on the Yellowstone bear safety Web page at nps.gov/yell/planyourvisit/bearenc.htm and in the park newspaper, which is distributed at all park entrances.