Quick sketchy ref for my sona's bird forms.
Normal wolf form: anthro/(no up to date feral ref)

In all forms, markings stay generally consistent with the wolf form ones, but if the anatomy forces a change they remain as similar as possible (in owl form the "mustaches" are almost fully white aside from the beginning, while the "eyebrows"/"horns" are gray with a fuzzy white lower margin; in the secretary bird form it does its own thing due to the lack of feathers in the nose-eye area).

Okami can change into these forms through the use of magic, the same that creates their's signature wings. In fact, Okami can transform in any living creature and, in a way, you could call them a "druid".
Form-changing is just temporary as it require constant use of magic, but these particular forms are sort of "default" for them as they require so little effort that Okami can even sleep in such forms.
It's also possible for Okami to "hybridize" their normal body with other forms, sort of like a griffin. What is valid as feral is also valid as anthro.

Also in the end I decided to drop Okami's grey goshawk form as a main form because I didn't really /feel/ it anymore.

(I will redo this in a more proper reference once I get to redo Okami's ref, but until then this will do. For the longest time the one thing that kept me from drawing Okami in bird form was the lack of a proper wing design.)