Warmer-than-normal winter temperatures may be to blame for bringing a grizzly bear out of hibernation early in Yellowstone National Park. The park confirmed a report of a grizzly eating a bison carcass on Feb. 9 in the central part of the park in Wyoming. 
 
 Yellowstone National Park spokesman Al Nash says the park is using this grizzly sighting as a reminder to visitors that they could encounter bears -- even during winter hibernation months. Nash says recent temperatures have been about 10 degrees higher than normal, and this is the earliest a Yellowstone grizzly has been sighted in the last five years. 
 
 In a press release, park officials warn skiers and hikers to be on alert and "stay in groups of three of more, make noise on the trail and carry bear spray." Nash says animals emerging from dens could soon be looking for food, and are attracted to areas where elk and bison that have died over the winter. 
 
 But grizzlies coming out of hibernation early -- especially around warm weather -- isn't as rare as you might think. 
 
 "Every year, we see occasional bears that come out in the middle of winter," says U.S. Fish and Wildlife Service grizzly recovery coordinator Chris Servheen. "Sometimes they come out because they didn't go into the den in good shape and bears that are very hungry and starving tend to come out in the middle of winter and wander around." 
 
 Servheen says bears go through a big physiological change before going into hibernation, and it takes a couple of weeks to get their bodies back to normal once they come out of the den. He says it's not unusual for a bear to come out for a warm period and then return to the den at the next snow storm. 
 
 But the biologist says since this Yellowstone grizzly has begun eating, it's probably been out for a couple of weeks and is unlikely to go back into hibernation this winter. 
 
 Find Frankie Barnhill on Twitter @FABarnhill 
 
 Copyright 2015 Boise State Public Radio 

 February 10, 2015 
 
 National Park Service 
 
 U.S. Department of the Interior 
 
 Yellowstone National Park 
 
 P.O. Box 168 
 
 Yellowstone National Park, WY 82190 
 
 
 
 FOR IMMEDIATE RELEASE 
 
 February 10, 2015 15-008 
 
 Al Nash 
 
 (307) 344-2015 
 
 YELL_Public_Affairs@nps.gov 
 
 ------------------------------------------------------------------------ 
 
 YELLOWSTONE NATIONAL PARK NEWS RELEASE 
 
 ------------------------------------------------------------------------ 
 
 Bears Starting To Emerge From Dens In Yellowstone 
 
 Blame the relatively mild winter weather for the early emergence of bears in the Greater Yellowstone area. 
 
 The first confirmed report of grizzly bear activity in Yellowstone occurred on February 9. A grizzly bear was observed late in the afternoon, scavenging on a bison carcass in the central portion of the park. 
 
 With bears emerging from hibernation hikers, skiers, and snowshoers are advised to stay in groups of three of more, make noise on the trail and carry bear spray. The same advice goes for those taking guided snowmobile trips in Yellowstone. 
 
 Bears begin looking for food soon after they emerge from their dens. They are attracted to elk and bison that have died during the winter. Carcasses are an important enough food source that bears will sometimes react aggressively when surprised while feeding on them. 
 
 Updated bear safety information is available on the Yellowstone bear safety Web page at http://www.nps.gov/yell/planyourvisit/bearsafety.htm and in the park newspaper distributed at all park entrances. 
 
 Yellowstone also implements seasonal bear management areas closures to reduce encounters between bears and humans in areas where elk and bison carcasses are in high density. A listing of these closures can be found at http://www.nps.gov/yell/parkmgmt/bearclosures.htm. 
 
 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 spotting scope or telephoto lens to get a closer look. All visitors traveling in the park away from developed areas should stay in groups of three or more, make noise on the trail, keep an eye out for bears and carry bear spray. Bear spray has proven to be a good last line of defense, if kept handy and used according to directions when a bear is approaching within 30 to 60 feet. 
 
 While firearms are allowed in the park, the discharge of a firearm is a violation of park regulations. The park’s law enforcement rangers who carry firearms on duty rely on bear spray, rather than their weapons, as the most effective means to deal with a bear encounter. 
 
 Visitors are also reminded to keep food, garbage, barbecue grills and other attractants stored in hard-sided vehicles or bear-proof food storage boxes. This helps keep bears from becoming conditioned to human foods, and helps keep park visitors and their property safe. 
 
 Bear sightings should be reported to the nearest visitor center or ranger station as soon as possible. 
 
 - www.nps.gov/yell - 

 Grizzly bears at Yellowstone National Park are emerging from winter hibernation weeks earlier than normal because of the arrival of spring-like weather, with warmer-than-usual temperatures and rain instead of snow, a park spokesman said on Tuesday. 
 
 Yellowstone on Monday confirmed the first report of a grizzly roaming the central part of the park, where it was seen scavenging on a bison carcass, according to spokesman Al Nash. 
 
 Nash said the emergence of grizzlies comes roughly a month earlier than in recent years, with the first sightings of the bears from 2012 to 2014 happening between March 4 and March 14. 
 
 Grizzlies are ravenous after periods of hibernation that can span months and in which eating and other activities are suspended, Nash said. The outsized, hump-shouldered bruins typically feed on the carcasses of winter-killed animals like bison, elk and deer for the quick intake of needed calories, he said. 
 
 The 2.2-million-acre (890,000-hectare) park that spans parts of Wyoming, Montana and Idaho is warning visitors to be on the lookout for the bears since they are not usually active during February, a month at the park that sees many fewer visitors than at the height of tourist season in the summer, Nash said. 
 
 “It’s important to make sure visitors during this period are aware that they already need to be thinking about proper actions in bear country,” he said. 
 
 That includes avoiding carcasses if seen, carrying bear spray, hiking in groups of at least three people and making noise to avoid startling bears and causing them to act defensively. 
 
 Grizzly bears in the lower 48 states were listed as threatened under the U.S. Endangered Species Act in 1975 after hunting, trapping and poisoning reduced their numbers to roughly 1,000 from about 100,000. 
 
 The Yellowstone area contains an estimated 600 grizzlies, or the bulk of such bears that still roam the lower 48 states. 
 
 A government panel that oversees Yellowstone-area grizzlies has said the population has recovered and should be stripped of federal protections, opening the way for hunting. 
 
 (Reporting by Laura Zuckerman in Salmon, Idaho; Editing by Cynthia Johnston and Eric Walsh)
– Visitors to Yellowstone in February typically don't need to worry about coming across grizzly bears. This year, however, they should be sure to pack the bear spray: Park officials say they spotted a grizzly feasting on a bison carcass on Feb. 9, roughly a month earlier than usual, reports Reuters. Unseasonably warm temperatures this winter are the likely culprit. “It’s certainly an indicator, but it’s not necessarily a rush of bears leaving their dens," a park spokesperson tells Grist. "If there’s one, though, it’s safe to assume that there will be others.” While it's not unheard of for a bear to leave the den briefly if it gets warm and then return when it snows again, the fact that this one was eating probably means that it's out for good, explains Boise State Public Radio. It is one of an estimated 600 grizzlies in the greater Yellowstone region, which accounts for more than half of the bears' total in the lower 48 states, notes Reuters. (At Yosemite, meanwhile, a near-extinct fox made a rare appearance.)