Crusty yellow matter on face

One of my birds in the loft, Helen, has yellowish crusty staining around one eye and on the cere. Just on the one side. She's acting normally, eating, etc. I haven't seen this before on any other birds. Any ideas what it is and what I should do about it? No sneezing, discharge or anything. I think I had noticed this once before on this same bird but it was slight and went away.

Here left side, the good side.

Sorry, no real ideas on what this could be.

Although... it does look like dried food - is she feeding young? ... just a thought.

Jen...what does her breath smell like? How are her poop? Does it have an odor?
How does the inside of her mouth look?

I'm thinking she could have a sinus infection which is also affecting her eye. The infection may be from canker or bacteria. Personally, I would start her on baytril and metronidazole.

Mouth clear, no odor. Poop has been fine. Some of the yellow on the cere looks like it came off so I think it's all from the eye. Or nostril maybe? It's not really as crusty as it looks in the picture. I just went to look and picked her up. She must weigh a pound and a half! What a big girl!

I would put her on baytril, Jen. Do you have some? If not, I can pop some in the mail tomorrow.