I'm not a veterinarian, none of us can diagnose your bird on the internet from a picture.
When did the eye symptoms start? What did it look like st the beginning?
Free ranging birds are highly dependent on accurate vision in order to capture prey and forage, to avoid predators, and to find suitable perches and shelter.
www.dvm360.com
But this is what I'm worried about
Except:
" Uveitis in birds is most often associated with trauma, infections, immune-mediated diseases, and neoplasia. Blunt or sharp trauma can cause anterior or posterior uveitis and hemorrhage (hyphema). Hypopyon, fibrin clots, and damage to the scleral ossicles can also be seen. Infectious causes of uveitis include encephalomyelitis, Marek's disease, reovirus, and poxvirus. Septicemia caused by any bacterial agent can be associated with uveitis. Clinical signs of anterior uveitis include photophobia, blepharospasm, corneal edema, aqueous flare, miosis, thickening or discoloration of the iris, and anterior or posterior synchiae. With posterior uveitis there may be retinal edema, hemorrhage, or detachment, or vitreous opacity. Treatment is aimed at the underlying cause as well as reduction of inflammation. Topical antibiotics and topical anti-inflammatory agents such as flurbiprofen are often used. Caution is advised for the use of topical corticosteroids such as prednisolone, especially for prolonged treatment periods, as they can be associated with local immunosuppression and secondary infections such fungal keratitis.":