page_title: History of wolves in Yellowstone
section_title: Annual wolf status since reintroduction
hierarchical_section_title: History of wolves in Yellowstone / Re-introduction (1995–present) / Annual wolf status since reintroduction
caption_attribution_description: English: Map of territories claimed in 2011 by the 10 packs of wolves that lived in Yellowstone National Park in the United States in that year.
context_page_description: When Yellowstone National Park was created in 1872, gray wolf populations were already in decline in Montana, Wyoming and Idaho. The creation of the national park did not provide protection for wolves or other predators, and government predator control programs in the first decades of the 1900s essentially helped eliminate the gray wolf from Yellowstone. The last wolves were killed in Yellowstone in 1926. After that time, sporadic reports of wolves still occurred, but scientists confirmed that sustainable wolf populations had been extirpated and were absent from Yellowstone during the mid-1900s.
  Starting in the 1940s, park managers, biologists, conservationists and environmentalists began what would ultimately turn into a campaign to reintroduce the gray wolf into Yellowstone National Park. When the Endangered Species Act of 1973 was passed, the road to legal reintroduction was clear. In 1995, gray wolves were first reintroduced into Yellowstone in the Lamar Valley.
context_section_description: Wolf population declines, when they occur, result from "intraspecific strife," food stress, mange, canine distemper, legal hunting of wolves in areas outside the park (for sport or for livestock protection) and in one case in 2009, lethal removal by park officials of a human-habituated wolf.
   *1995-99 Data reflects status of the wolf in the Greater Yellowstone Ecosystem. Since 2000 monitoring has focused on packs operating within park boundaries. Wolves continue to spread to surrounding areas, and the last official report by the park for the Greater Yellowstone Area counted 272 wolves in 2002.
caption: Yellowstone wolf pack territories in 2011
exif: {}