"Sled dogs at rest" by US Department of State is licensed under CC BY-NC 2.0
Text from the back cover:
Stolen from his comfortable California home, Buck -- a powerful half-St. Bernard, half-Scottish sheepdog -- is shipped to the Klondike and pressed into service as a sled dog. So begins an odyssey in which Buck suffers cruelty and neglect, learns the brutal skills of a survivor, finds a gentle master that he can respect and love, then leaves civilization behind to become the legendary leader of a wolf pack.