Frederique Olivier / Female Ostrich (Struthio camelus) grazing, Ngorongoro Crater, Tanzania

Alan Murphy/ BIA / Northern Bobwhite (Colinus virginianus) male having feathers ruffled by wind, Texas

Aflo / Hawfinch (Coccothraustes coccothraustes) perched on frosty branch, Mukawa, Hokkaido, Japan,

Krijn Trimbos / Great crested grebe (Podiceps cristatus) in courtship display posture, The Netherlands, March.

Claudio Contreras / Inca dove (Columbina inca) perched, with feathers fluffed up. Xochimilco wetlands, Mexico City, Mexico. September.

Alan Murphy / Northern Bobwhite (Colinus virginianus) male having feathers ruffled by wind, Texas

Mark Hamblin / 2020VISION / Female Chaffinch (Fringilla coelebs) perched in falling snow, cleaning its beak, feathers being ruffled by wind, Inverness-shire, Scotland, UK, December 2011

Mark Hamblin / 2020VISION / Male Chaffinch (Fringilla coelebs) perched in falling snow, feathers being ruffled by wind, Inverness-shire, Scotland, UK, December 2011

Jussi Murtosaari / Nutcracker (Nucifraga caryocatactes) perched on snowy branch, Ounasvaara, Rovaniemi, Lappi / Lapland, Finland. January

Markus Varesvuo / Linnet (Carduelis cannabina) adult male, Uto, Finland, August

Markus Varesvuo / Fox Sparrow (Passerella iliaca) Uto, Finland, December

Loic Poidevin / Greater Flamingo (Phoenicopterus roseus) juvenile with ruffled feathers, Camargue, France, May