Gray Wolf Canis lupus in Yellowstone National Park, USA. This is the Hayden Pack, consisting of alpha female 540F and alpha male 541M and 6 other offspring from this pair note the radio collars on each alpha wolf. Here they are crossing the Yellowstone River in Hayden Valley.These wild wolves were re-introduced to the park in 1995 14 animals and again in 1996 17 animals.

Credit to: BluePlanetArchive / Michael S. Nolan

Image dimensions: 5324x3550