"Seekers: Smoke Mountain" by Erin Hunter (Seekers, Book 3)

The third book in a thrilling animal fantasy series following the epic journey of three bears, from the #1 nationally bestselling author of Warriors.

United at last, polar bears Kallik and Taqqiq, black bear Lusa, grizzly bear Toklo, and Ujurak, the mysterious shape-shifting bear, learn of a place they think must be the destination of their quest: the Last Great Wilderness. But getting there means crossing the burning Smoke Mountains, which hold obstacles more treacherous than anything they've faced so far….

For fans of Warriors, Survivors, and animal fantasy series like Wings of Fire and Foxcraft, Seekers is a sweeping and incredible journey through the beautiful, dangerous world of wild bears.