The sparrows in the hedgerow. Pastoral parable offers nature lore plus suspense

The Heart of the Valley, by Nigel Hinton. New York: Harper & Row. 236 pp. $15.95. The life of the tiny hedge sparrow doesn't normally suggest tension and terror. But in his most recent novel - and his first written for adults - Nigel Hinton has set out to show us that sparrows lead lives that challenge those of modern men and women for sheer excitement.

The setting is an English valley, the kind often reproduced on postcards: picturesque and a bit quaint. The characters: two hedge sparrows, a few rural rustics, and an assortment of minor actors ranging from the local fox to a very benign farm dog. And, I hasten to add, a villain of monstrous proportions who manages to out-terrorize the creations of Stephen King.

The plot is starkly simple: What happens in the life of two sparrows who meet, mate, and try to raise a family in the seeming peace and quiet of a rural valley? What elevates the account beyond the level of a children's story is primarily the vivid details Hinton blends with the elements of plot. One can only assume that he has watched, closely and lovingly, the behavior of bird and beast. The book is freighted with fascinating bits of information and we learn - and delight in the process - everything from the eating habits of the sparrow to its nest-building logic.

When the villain comes on stage, the book takes a sudden turn, transforming itself from a lyric pastoral into a thrilling tale of suspense that, for most readers, should make it almost impossible to put down. But how unlikely a villain: a newly hatched chick, a cuckoo. It's one of the startling things we learn about life in the heart of the valley. The female cuckoo builds no nest of her own but lays her eggs in those built by other species of bird, one egg per nest. The hatched chick is tended by the foster parents just as though it were one of their own.

But the cuckoo's inbuilt urge for survival - even as a newly born chick - leads it to drive the other chicks, the actual offspring, from the nest. Thus the cuckoo becomes, to the somewhat puzzled foster parents, their sole offspring. This is what happens to the two sparrows who haunt the pages of Hinton's novel. We watch in amazed horror as the female cuckoo waits for the moment to deposit an egg in the sparrows' nest. The pages that follow recount the warfare between the sparrow chicks and the intruder. They are as gripping as any I recall reading.

In fact, were one to read aloud to children from this book - and there are many suitable parts - these sections might best be edited out, they are that forceful.

Hinton is relentless in showing us the world at the heart of the valley. This is not the world of Walt Disney's animal kingdom; the foxes here are always hungry, and territorial rights are constantly being declared. Here the casual nudge of the hedge by a passing truck brings down a nest constructed with care and skill, shattering the sparrows' first attempt at a family.

Hinton's essentially dispassionate and quite unsentimental presentation succeeds brilliantly in heightening our awareness of the vast and complex world of little lives that surround our own. It succeeds as well, and surely this was a part of the author's intent, in expanding our compassion, in orienting our view just a bit away from a total fixation on ourselves.

That the novel's parallel story of human lives in the valley seems contrived and artificial, especially in its obvious attempt to echo at a more profound level the meaning imbedded in the story of the two sparrows, does not ultimately detract from its appeal.