conjunction with other National Forests and National Parks within the Greater Yellowstone Ecosystem, works cooperatively to maximize human safety and to ensure habitat protection for both species of endemic bears. Visitors are mandated to store their food in their vehicles or in steel containers found in campgrounds, and bear-proof trash receptacles are located in the front-country zones throughout the forest. In the backcountry, food must be stored some distance from campsites, and other related precautions are enforced to help prevent bad encounters. Cougars and timber wolves are large apex predators that inhabit the forest. Since the 1990s wolf reintroduction program in Yellowstone National Park, wolves have migrated into the forest and established permanent packs. Approximately a dozen wolf packs totaling 70 individual wolves were documented in the forest in 2012. The wolf was delisted as endangered once their population levels had reached management objectives and limited hunting of wolves was permitted in the forest starting in 2012. Cougars are generally nocturnal and rarely seen but hunting of this species is also allowed in highly regulated harvests. Wolverines are rare and elusive so documentation is often only from their tracks. The Canada lynx was native to the forest, but no known populations may still exist due to the rarity of its primary food source, the Snowshoe hare. Shoshone National Forest is considered critical habitat for lynx recovery since the species is listed as threatened under the Endangered Species Act and the forest is in their historical range. Other generally carnivorous mammals include coyote, bobcat, weasel, marten, ferret and badger. Omnivorous mammals such as the raccoon and skunk and herbivore mammal species such as the porcupine and pika, are common to the forest. The beaver is considered a species of special interest to Shoshone National Forest since its dam building activities improve habitat for numerous other species such as the moose, breeding waterfowl, various amphibians and other species dependent on a riparian environment. Native herbivores such as the moose are found in small numbers near waterways, especially at lower elevations. Moose populations in northwestern Wyoming and other areas of North America have been on the decline since the end of the 20th century, possibly due to a parasite. There were an estimated 739 moose in the forest in 2006 which is almost 300 fewer than there were 20 years earlier. Other ungulate species are much more common and there are over 20,000