Have you noticed any spawning?
Bass should be done by now, but beds would be noticable.
Bluegill spawn should be hot now.

You should try feeding the BG with floating fish food. This will give you a better indication of numbers vs hook and line. I though my lake was scarce with BG, now I have about a million under my dock. Go figure.

I am not sure of the dynamics of turtles, but that seems like a lot for that size pond. They can eat a lot of fish, along with the birds. Is there much cover for forage fish to hide from predators?