Nature-writer Pringle turns to a naturalist's biography in this account of ""wolf-man' David Mech, a wildlife biologist by training and early inclination, who began his career in 1958 observing the wolf-moose relationship on Lake Superior's Isle Royale. That first summer Mech never saw a wolf, but the next year he began spotting wolves and moos from the air and in 1960 first saw wolves actually kill a moose. More common, however, were chases from which the moose escaped; and those killed, Mech found, were the weak and diseased--attesting to a balance in the two populations. Later, in a Minneapolis suburb, Mech adopted two wolf cubs, watched their unusually rough battle for dominance, and concluded as the one survivor grew (the male died of distemper) that wolves should never be pets. Later, radio-tracking wolves in Northern Minnesota's Superior National Forest, Mech made important discoveries about territoriality and the relationship between wolves and deer populations. ""Under normal conditions,"" he found ""a wolf pack seldom enters alien territory, even if chasing prey."" And in bad times when both deer and, consequently, wolf populations were starving, surviving deer tended, for safety, to gather in the ""buffer zones"" between wolf packs' turf. Concentrating on the observations, Pringle gives readers a first-hand look at wolf dynamics and a sense of how field observations are made.