Abstract We report the discovery of a nest of Montagu’s harrier ( Circus pygargus ) in northwestern Italy containing three chicks: one normally coloured with white down and two dark morph individuals with grey down. The nest was discovered during wheat harvesting and, because it was left unprotected, the chicks were collected and transferred to a wildlife rehabilitation centre. During captivity, the two grey chicks developed an almost entirely black juvenile plumage. Dark morph individuals are relatively common in Spain but are very rare in other European countries. To our knowledge, dark-morph downy chicks of Montagu’s harrier have been very rarely described and illustrated.
Boano et al. (Sat,) studied this question.