The texture of the fur is perfect! A lot of action in there, this picture tells a story. It show a moment of goofyness for these usually "so proud" animals. It is nice to see them in action other than just posing as you expect a wolf to pose in a "I'm a proud and free wolf" style.
Good usage of the telephoto lense! Wolves in action are not easy to catch as they move fairly quickly! A personal opinion would be to seek a different background to make it more "natural" but I don't know in what kind of environment they are, so this is a personal preference only. Great work overall