Ok, at the bottom of the field guide are screenshots with pillars with pictures on them of birds. Now, I'm assuming that since there is no explanation on the page we havent figured this out yet.
My first theory is that the ball looks slightly like a sun. The lines radiating away from the bird could be heat. The bird itself could be a pheonix......the code name of bungies project which I personally know nothing about. If its really even a project.
Or, perhaps the giant ball could be the Comet rising out of the east (was it east?). The bird itself could be a representation of the spirit of either the hero or the leveller (i'm going with hero, since the comet seems to signal the arrival of the hero and i believe that the eruption of tharsis signals the arrival of the levellor).
Any thoughts?