This is the ultimate beachcomber's book. A series of meditations prompted by walking on the wild estuarial beaches of Ainsdale Sands between Blackpool and Liverpool, Strands is about what is lost and buried then discovered, about all the things you find on a beach, dead or alive, about flotsam and jetsam, about mutability and transformation - about sea-change.

Every so often the sands shift enough to reveal great mysteries: the Star of Hope, wrecked on Mad Wharf in 1883 and usually just visible as a few wooden stumps, is suddenly raised one day, up from the depths - an entire wreck, black and barnacled, and on either side two more ruined ships, taking the air for a while before sinking back under the sand.

And stranger still, perhaps, are the prehistoric footprints of humans, animals and birds on the beach: prints from the Late Mesolithic to mid-Neolithic period which are described as 'ephemeral archaeology' because they are preserved in the Holocene sediment, revealed briefly and then destroyed by the next tide.

Strands describes a year's worth of walking on the ultimate beach: inter-tidal and constantly turning up revelations: mermaid's purses, lugworms, sea potatoes, messages in bottles, buried cars, beached whales and a perfect cup from a Cunard liner. Jean Sprackland, a prize-winning poet and natural storyteller, is the perfect guide to these shifting sands - this place of transformation.