Winter Study (Anna Pigeon Series #14)

Soon after Anna Pigeon joins the famed wolf study team of Isle Royale National Park, giant wolf prints are found, and she spies the form of a great wolf from a surveillance plane. When a female member of the team is savaged, Anna is convinced they are being stalked, and what was once a beautiful, idyllic refuge becomes a place of unnatural occurrences and danger beyond the ordinary.