I just got a really close look at him, and his nostrils, at least one, looks clogged with dirt. It's dark brown, the color of fir bark dust. He would also 'burp' a bit but not the forceful sneeze I hear when I hold him in the morning. One side of the mouth would pop open, it seems only on the exhale. It's not a gaping wide open mouth breathing.

I'm hoping the shed will help clear the nose, and everything really.