They range from a pocket insect guide to a glossy television series spin- off, from an unusual appeal to go easy on pests to an intimate tour of Britain's wild places, and from a long documentary on coral reefs to the drama of a pair of hawks nesting in the middle of a big city.
The pounds 5,000 prize, which is in its third year, is an amalgamation of two long-standing competitions, BP's Sir Peter Kent Book Prize and one run for several years by The Natural World, the mazine of the Wildlife Trust.
A panel of five judges has chosen a shortlist of six, featuring the work of an eclectic group of authors: a Canadian professor, two American journalists, a brace of British writer-illustrator teams and David Attenborough.
The tome of the grand old man of British wildlife is sure of a prominent place in the shops, regardless of whether he scoops the prize tomorrow. Sir David's The Life of Birds is the sumptuously produced spin-off of his sumptuous television series on bird behaviour. It is expected to be extremely popular.
Rita Schreyer, commercial director of Books Etc, said the company's most successful book-signing session was for Sir David's other spin- off, Life on Earth. "He was there all afternoon and signed nearly a thousand copies," she said.
But not only much-hyped TV-related books about the environment can be massive sellers. Two years ago Richard Mabey's Flora Britannica, a magisterial account of Britain's wild flowers and their folklore, which feels like a concrete slab and costs pounds 30, sold about 80,000 copies. It was shortlisted for the first BP Natural World prize.
Could there be another Silent Spring hidden in this year's list, another Ring of Bright Water? The chairman of the judges, the environmental journalist Linda Bennett, said they were looking for a book that was "a significant work" and, most of all, it had to be accessible.
"We want people to understand more about conservation, so we want them to have lively text, and to read about conservation like they might read exciting, sexy novels," she said.
Exciting and sexy might not be the first adjectives one would apply to Nature Wars, Mark Winston's study of pest-control regimes and his conclusion that we should go easier on pests.
But it is a compelling argument and certainly lively, as are Marie Winn's account of hawks nesting in the heart of New York, Red-Tails in Love, and Osha Gray Davidson's documentary on coral reefs, The Enchanted Braid.
A new field guide to Britain's dragonflies and damselflies, by Steve Brooks and Richard Lewington, may seem to be the most lightweight contender of all for the BP Natural World Book Prize.
But the slim volume, filling a gap in the literature, is a jewel of a book and the one your correspondent would make the winner. It is informative, authoritative, imaginative, accessible and beautiful.
You don't fancy reading about dragonflies? Pick up this book and you just might change your mind.
The Main Contenders
The Life of Birds by David Attenborough (320pp, BBC Books, pounds 18.99)
The book of the Old Whisperer's current television series: a detailed manual of behaviour rather than a twitcher's guide. His descriptions and vivid photographs prove an absorbing combination: a black heron fishing with its wings wrapped around it like a toreador's cloak, a short- toed eagle disgorging a snake it has carried back to its chick. Sir David Attenborough, 72, is the doyen of British wildlife film-makers. He has been grabbing the attention of viewers since his Zoo Quest series in the Fifties.
The Enchanted Braid [Coming to Terms with Nature on the Coral Reef] by Osha Gray Davidson (269pp, John Wiley pounds 19.99)
Coral reefs, US Senate hearings were told in 1990, may be the first ecosystems to be destroyed by global warming. Three weeks ago leading coral scientists said unprecedented sea temperatures this year killed vast areas of coral in the Indian Ocean and the South China Sea, a warning passionately argued in this book.
Osha Gray Davidson is an American reporter who writes for The New York Times, New Republic and other journals.
Natural Heartlands by Kenneth Taylor and David Woodfall (146pp, Swan Hill Press, pounds 24.95)
A full-colour examination of how people affect the ecosystems or natural habitats peculiar to the British Isles. A book that might fit the coffee- table category, so striking are its photographs (by Woodfall), if the essays (by Taylor) were not so engaging.
Kenneth Taylor is a naturalist, writer and broadcaster.
David Woodfall is an environmental, landscape and wildlife photographer.
Nature Wars [People v Pests] by Mark L Winston (210pp, Harvard University Press, pounds 15.50)
Pests are not creatures for which we may feel much sympathy, but all those cockroaches, weevils and munching moths are members of the natural world. If we declare war on them we can do untold damage. Thirty-five years after Silent Spring alerted the world to the dangers of DDT we are still awash with pesticides.
Mark Winston, Professor of Biological Sciences at Simon Fraser University in British Columbia and author of The Biology of the Honey Bee and Killer Bees, outlines a new management, not eradication, approach to pests.
Red-Tails in Love [A Wildlife Drama in Central Park] by Marie Winn (309pp, Bloomsbury, pounds 13.99)
Anyone who has watched kestrels nesting on blocks of flats knows the thrill of birds of prey in the city. It happened to New Yorkers in the spring of 1992 when a pair of red-tailed hawks built a nest on a Fifth Avenue ledge. Birdwatchers in Central Park, where the hawks hunted, became obsessed and the story is about them as much as the birds.
Marie Winn writes a column on the natural world for The Wall Street Journal and has written books on the effect of television on children. She lives in New York City and spends time each day in Central Park.
Field Guide to the Dragonflies and Damselflies of Great Britain and Ireland by Steve Brooks and Richard Lewington (160pp, British Wildlife Publishing, pounds 18.95)
The slimmest book on the shortlist, but perhaps the most enchanting. A beautiful, technical guide to Britain's 38 resident and 9 migrant species of dragonfly and damselfly, with descriptions, notes and maps.
Steve Brooks became curator of the dragonfly collection at the Natural History Museum. He lives in Hertfordshire.
Richard Lewington illustrated The Butterflies of Britain and Ireland. He lives and works in Oxfordshire.Reuse content