This information is awaiting authentication by a species expert, and will be updated as soon as possible. If you are able to help please contact: arkive@wildscreen.org.uk
Glossary
Casque: A helmet-like structure or protuberance.
Coverts: small feathers concealing the bases of larger primary feathers, usually on the wings or tail.
Mantle: in birds, the wings, shoulder feathers and back, when coloured differently from the rest of the body.