BTO Abnormal Plumage Survey

Blue Tit with an all-dark head, a condition known as ‘melanism’ (photo: Andrew Cook)

“Welcome to the BTO’s Abnormal Plumage Survey, a study looking at abnormal plumage of British and Irish garden birds.

This survey has been set up to allow you to report observations of birds in gardens showing unusual plumage characteristics, notably those associated with pigmentation problems. Plumage abnormalities associated with feather loss are NOT being recorded through this survey.”

If you see birds with unusual plumage, use this link to complete the survey: BTO Abnormal Plumage Survey