"Sunday Morning" took viewers today to watch wolves in Yellowstone National Park. The footage was by videographer Judy Lehmberg.
Gray wolves nearly became extinct by the mid-20th century, as they were killed by the thousands during the settlement of wild lands in North America. They would become protected under the Endangered Species Act in the mid-1970s, but they had been virtually extirpated from Yellowstone long before.
In the 1990s the Yellowstone Wolf Project reintroduced wolves into the park, in an attempt to right an ecosystem in which a key predator had been removed. Thirty-one wolves were captured in Canada and released into the park between 1995 and 1996. At it peak, in 2004, the wolf population in Yellowstone numbered 174.
The long-term health of the park's wolves is monitored by the Wolf Project, in order to learn more about the animal's relationships with key species and the overall health of the ecosystem.