The Wolfer — Loren D. Estleman

Known and feared throughout the West, wolfer Asa North is as ferocious and ruthless as the wolves he hunts. But he may have finally met his match in Black Jack, the cunning, blood-thirsty beast whose pack has ravaged innumerable herds of sheep and cattle. Despite the large bounty offered for his pelt, Black Jack remains on the loose--and ranchers in Idaho Territory continue to live in fear.

Hungry for money and blood, North sets off in pursuit of this wily and savage creature, accompanied by an East Coast journalist who wants to immortalize his mission. But their journey is a perilous one, for there are other men on Black Jack's trail. Men who will let nothing--and no one--stand in their way...