That trip and subsequent ones led to “People of the Deer” (1952), a book about the struggles of the Ihalmiut, an Inuit group in the Northwest Territories.

At a time when the Arctic was largely a distant mystery to the rest of Canada, the book brought Mr. Mowat legions of both admirers and political enemies in the south, where his findings were debated in Parliament. In a review of Mr. Mowat’s follow-up book, “The Desperate People,” Walter O’Hearn, writing in 1959 in The New York Times, called the author “Canada’s angriest young man.”

In “Never Cry Wolf,” Mr. Mowat learned about the lives of wolves with binocular clarity, about their treks to find food in winter and their territorial claims in summer, when they remain in their dens living on mice. (Mr. Mowat, in the interests of science, tried living on them, too, and found the diet nourishing.)

He portrayed wolves as patient and gentle with their own, sometimes even fond of practical jokes. They adopted orphan puppies and babysat for other wolves’ pups. They never killed more than they could eat.

In one passage, he described the father of the wolf family he was observing, calling him George. “His dignity was unassailable, yet he was by no means aloof,” he wrote. “Conscientious to a fault, thoughtful of others, and affectionate within reasonable bounds, he was the kind of father whose idealized image appears in many wistful books of human family reminiscences.”

George, he added, was “the kind of father every son longs to acknowledge as his own.”

Elizabeth May, the leader of Canada’s Green Party and a longtime friend who had joined Mr. Mowat in environmental campaigns, said that much of the power in his books came from a lack of overt preaching.