From 1839 until 1940, the letters pages of The Times bore traditional witness to the cuckoo’s first call of spring. In his synoptic survey of all things avian, Birds Britannica, Mark Cocker records that on 6 February 1913, one correspondent, R Lydekker, FRS, proudly announced: ‘While gardening this afternoon I heard a faint note which led me to say to my under-gardener, who was working with me, “Was that the cuckoo?”’ This scene – which sounds more like a Harry Enfield sketch to modern ears – was supplanted six days later. In a second letter, Lydekker was forced to admit that, ‘in common with many other persons, I have been completely deceived’. What he’d actually heard was a bricklayer imitating the bird. It was an ironic deception, since the cuckoo itself relies for its very existence on mimicry.

Why is the cuckoo so firmly lodged in our culture? Part of the reason is that evocative two-note call, which sounds so close to the human voice that Lydekker mistook one for the other. But perhaps we also sneakingly admire the way it lays its eggs in other birds’ nests, where its progeny grows fatter than the hosts’ own chicks – which are turfed out of the nest, tumbling to their deaths. On and on the cuckoo chick begs, its voracious gape opening ever wider for grubs. Do we respect such a parasite for its ingenuity? Or do we look on with a kind of fascinated horror at this avian benefit cheat, succoured on another’s charity?

To address this question and many others, Cambridge zoologist Nick Davies offers the fruit of thirty summers spent on Wicken Fen. He paints a vivid portrait of the place, evoking the spirits of Hereward the Wake and the floating ship of Ely Cathedral. Here, in this liminal zone – neither