Over the years we have been contacted repeatedly by rescuers and lay people, who were caring for corvids such as magpies, jackdaws and crows, and who observed that their foster birds showed difficulties with flying despite appearing otherwise fit and healthy. Some of these birds demonstrated abnormal flight feathers and showed an unusual or even abnormal behaviour not normally expected in wild birds. A closer assessment of the plumage showed quite quickly that these birds had been wing clipped.
The Science Behind Caramel Crows
This fascinating blog post by Kaeli Swift gives some detailed insight into the topic of what controls feather pigmentation in birds, and in particular corvids.
Shared with the kind permission of Kaeli Swift of Corvid Research.
Generally, when I receive emails with the subject line “interesting crow” it’s because the author noted some peculiar or amusing crow behavior they want to share, or because they spotted an unusual looking crow due to AKD, leucism or avian pox. Rarely, it’s for none of these reasons and is truly a horse of a different color. Or in this case, crow.[…]
via The science behind caramel crows — Corvid Research