Wood Warbler Phylloscopus sibilatrix

The Wood Warbler, Phylloscopus sibilatrix, is the largest of Britain’s leaf warblers, belonging to the family Phylloscopidae, and one of the most beautiful summer migrants to grace British woodland. Adults are strikingly tricoloured – bright yellow-green above, with a vivid sulphur-yellow supercilium and throat, and pure white underparts – a combination that sets it apart from all similar species. It is a specialist of mature, open-structured deciduous woodland with a closed canopy, sparse shrub layer, and deep leaf litter, favouring oak and beech woodland in upland and western Britain. The song is extraordinary – a shivering, accelerating trill that builds to a spinning crescendo, often delivered whilst the bird quivers its wings on a bare branch. The Wood Warbler has declined sharply and is a Red List species, having largely retreated to western Britain. Image: © Natural England/Allan Drewitt, Flickr.

Find out more: RSPB, Suffolk Wildlife Trust, iNaturalist