Cuckoo Cuculus canorus

The Cuckoo, Cuculus canorus, is one of Britain's most familiar yet increasingly elusive summer visitors, belonging to the family Cuculidae and arriving from sub-Saharan Africa each spring. Adults are distinctive – blue-grey above with finely barred white underparts, and a long tail lending them a superficial resemblance to a Sparrowhawk in flight that may serve to alarm nesting birds. The species is an obligate brood parasite, laying its eggs in the nests of other species – particularly Meadow Pipit, Reed Warbler, and Dunnock – with each female specialising in a single host species and producing eggs that closely mimic those of the host. The male’s familiar two-note call is one of the most culturally resonant sounds of the British countryside. The Cuckoo has declined steeply across much of Britain and is a Red List species, with research suggesting that deteriorating conditions on its African migration route and wintering grounds are a significant factor. Image: © Neil Rolph, Flickr.

Find out more: RSPB, Suffolk Wildlife Trust, iNaturalist