Jimmy, maybe Zep will see this and be of some help. His soil is probably very similar to what you have, and maybe he'll have some experiences to share with his water level changes.
This general area's pretty diverse as far as soil goes. In a 30 mile radius there's black gumbo, sugar sand, and red clay that gets as hard as concrete when dry. I have the red clay/sand mix and I've drilled post holes 10' from the pond edge, and hit water 2 or 3 feet down. That's a lot of natural absorption.
I might cut the pump off for a few days, and see if the pond seeks it's own level. If it drops a foot and then quits dropping, then maybe it's absorption or a leak closer to the shoreline. If the water continues to keep dropping, then I might be worried.
