The Last Mammoth — Manly Wade Wellman

Sam Ward was yearning for adventure when a Cherokee man arrived from a distant village with a tale of a monstrous hairy creature threatening his land. The formerly peaceful beast went rogue upon the death of its mate, and the chief of the Twilight People sent Otter to ask for help. Sam's quest quickly turns dangerous with new challenges and new enemies, but using their wits, skills, and courage, Sam and Otter finally face Giluhda, last of the living mammoths.