Country diary: this bird could be spooked by its own shadow

Rockland Broad, Norfolk The water rail's distressed call tells you everything about its solitary life buried in deepest cover

As the light falls in my neighouring parish and the mercury drops, so the bird sounds acquire extra layers of intensity. I'm thinking of the hysterical chinking of blackbirds in the ivy and the disembodied sharp pitt notes of Cetti's warblers. Most evocative of all, however, are the water rails.

Related to the moorhen and coot, this arch introvert is long-legged and long-billed, with a curious laterally compressed body that enables it to thread tiny gaps between reed stems. It is common in our valley but I seldom see one. Tonight there are four, and the way they answer each other's sounds at 100-metre intervals across the marsh tells you everything about their solitariness and oddity.