During the Great Flood, many creatures appear to have been buried and then reburied weeks or months later. This is one evidence supporting the “continent-crossing tidal waves” contentions regarding the Flood.
Perhaps not all land, all the time, was under water. Perhaps it was a series of tidal waves; worsening and lessening. Noah waited for months after landing in the mountains of Ararat before opening the door and exiting. He successively released birds. Isn’t that interesting? Perhaps (by theory) it was because he did not know if another severe tidal wave would lift and carry them again to land (again) later.