The race of sunbirds is sacred to Mithros. The Sunbirds are divine creatures, made only to live in the Divine Realms. There are a bunch of them, but it's rather unusual to see one. As far as it is known, they are not found in the Mortal Realms; it would no doubt be interesting if one found it's way there, or was brought there. The circumstances of such a thing would be suspect, however, as if you kidnapped sunbird, there's a very good chance that, as soon as Mithros discovered the deed, you’d only be a wee greasy scorched mark, and the sunbird would be home.
As far as we know, the Sunbirds are not gods.