Wren on the Wall (gouache style)

The wren, Troglodytes troglodytes, is one of the UK's commonest breeding birds, though it's small and secretive enough to be heard far more often than seen. Its scientific name means cave dweller, a nod to its habit of creeping into crevices. Look for a round, warm-brown bird with fine barring, a pale stripe over the eye and a stubby tail held upright. The song is fast, loud and full of trills.

Wrens feed on insects and spiders, so a garden with plenty of cover suits them: dense shrubs, ivy on walls, log piles and leaf litter left under hedges. In spring the male builds several domed nests of moss and leaves, and the female chooses one to line with feathers. Avoid trimming ivy and hedges between March and August, when birds may be nesting. In hard winters wrens sometimes roost together in a nest box to share warmth, so a box put up in autumn can be useful long before spring.

A wren with its tail cocked stands on a mossy stone wall among ferns and small flowers. Old walls like this, full of gaps and soft with moss, are just the kind of place wrens hunt and nest. The cocked tail is the giveaway, the one detail that tells you what the bird is before you've had a proper look.