A female Bald Eagle (Haliaeetus leucocephalus) preens herself from the branch of a dying ponderosa pine. When she scratched around her face with long and dangerously sharp talons, a nictitting membrane protectively covered the eye. Bald eagles and birds of prey of Eastern Oregon, and the PNW.

A female bald eagle roosts on branch of a dead ponderosa pine, while she preens herself. Note the semi-opaque membrane covering the eye, tihs is called a nictitating membrane, and is used to protect the eye from abrasion. Deschtues County, Crooked River Canyon, Eastern Oregon.