BRIGHTNESS FEATURES OF VISUAL SIGNALING TRAITS IN YOUNG AND ADULT EURASIAN EAGLE-OWLS.

The article discusses a study which investigated the signaling role played by achromatic plumage patches and examined the patterns and characteristics of the brightness of Eurasian eagle-owl's white feather patches for adult and young birds. The study collected blood from breeders and young birds and measured the brightness of their white plumage. Results revealed that the total reflectance of the white feathers in young birds differed from that of the white feathers in adult owls and the brightness was distinct between the sexes only in adults.