I read this book years ago and loved it. Nothing has changed. The audiobook was fantastic. 

Wolves are amazing creatures, and I feel that this book exemplifies that fact.  The author even discusses how they changed the Yellowstone environment for the better. Reintroducing the elk's natural predator allowed Willow trees to recover, creating a cascading ecological effect that improved the natural landscape. It's astounding. 

These little factual tidbits were sprinkled into '06's story. Although she would later become collared and become officially known by that collar number, the heroine of our story was born in 2006 and was nicknamed 06. As park rangers and visitors alike were able to follow her through their scopes, she became one of the most famous wolves to emerge out of the Yellowstone reintroduction program.  Her story is inspiring and sad, and one worth knowing.