A large percentage of this birds population lies with Radipole Lake and Lodmoor in Weymouth, Dorset.
In Europe this small passerine bird is mainly resident throughout the year, but eastern populations migrate short distances, wintering within the breeding range.
It is a bird of dense vegetation with scrub, usually close to water, such as a reedbed with bushes, or a small area of riverside woodland. The nest is built in a bush near water, and 3-6 eggs are laid.
This is a medium-sized warbler, 13–14 cm (5–6 in) long. The adult has a plain reddish-brown back, a pale stripe over the eye, whitish grey underparts, a broad tail and short wings. Structurally, it resembles an oversized Wren. The sexes are identical, as with most warblers. Like most warblers, it is insectivorous. This bird is named after the Italian zoologist Francesco Cetti.