A girl, or a young woman, melts the heart of a frosty old misanthrope.

Isn't that one of the oldest stories there is? It certainly seems that way, although repeated broadcasts of Heidi in the 1970s may have helped to give that impression. It would have been so easy for Alice Greenway to have written just another variation of that story, but she's chosen instead a harder, bolder path.

The young woman who appears in Jim Kennoway's life is not there to get him to learn to love again, nor to bring redemption or closure, but inadvertently to confront an ill and embittered man with his past, forcing him to reflect on his actions and consider their weight.

The novel takes place over the summer of 1973 on Penobscot Bay in Maine. After a career of cataloguing (and skinning, stuffing and mounting) birds for the American Museum of Natural History in New York, 70-year-old ornithologist Jim Kennoway has retired to his family's old summer house following a leg amputation. Alone, he drinks heavily, smokes and neglects his health. It's been months since he retired, but his former colleagues still can't stop talking about him, his taciturn manner and irascibility, as well as his brilliance, having elevated him to legendary status.

During the war, he was stationed in the Solomon Islands. His commanding officer assigned him to a deserted island to observe and report back on Japanese naval activity, reasoning that it was the kind of solitary gig well suited to a man who was in his element skulking silently through forests looking for birds. On this mission, Jim met the islander Tosca, then only a 15-year-old boy, and they struck up a friendship, Kennoway eventually bequeathing Tosca his set of bird-skinning tools.

Three decades later, Tosca is a proud father, with a daughter named Cadillac, who is about to start medical school in the United States. Tosca has asked if she can come and stay with Kennoway for a while to acclimatise her to the new country, and, in some alcohol-fuzzed moment, the old man consented. But with his mobility restricted by the loss of his leg, his free-spirited wife long dead, his career over and nothing to look forward to, Jim is crabbier than ever before.

Even the presence of his own son winds him up and sets his teeth on edge. He doesn't want company, not even that of a striking young black woman from the very islands that enraptured him as a young man. If he can't cope with the present, Jim thinks, he certainly doesn't need someone throwing the past in his face.

Actually, it's not quite true that Jim has nothing to live for. There is one unfinished project that's keeping him going: an article expounding his theory that Robert Louis Stevenson based Treasure Island on Old Providence, an island off the coast of Nicaragua. Ah, Treasure Island. When someone reads it for the first time, Jim reflects, they identify with Jim Hawkins. When they return to it in later life, it's Long John Silver that they feel closest to. And that's especially true of the emotionally scarred and now one-legged Jim Kennoway.

Treasure Island isn't The Bird Skinner's only literary antecedent. Hemingway also casts a long shadow over this novel, with its imagery of a surly old man diminished by the loss of his physical strength and potency working away in his boathouse on the very model of typewriter that Hemingway favoured. And there are echoes of Conrad's Heart Of Darkness too, as Jim recalls more and more of his wartime experiences with Cadillac's father in the South Pacific.

Cadillac's presence may soften Jim up a bit, but the trajectory of Greenway's narrative is never down the path of true redemption, or even a tying-up of loose ends. The author is far too true to Jim's character to indulge in the kind of sentimentality that he would be unable to tolerate.

But Greenway deals with her characters with such sensitivity and understanding that the emotional payoff, which there is, feels justly earned.

Alice Greenway is at the Edinburgh International Book Festival on August 20 at 2.30pm