Recently I have been targeting big catfish using live bluegill. Unfortunately my first 2 spots have a large concentration of turtles. So my live bluegill are no longer live and have their heads and guts missing.

Am I possibly not rigging my bait correctly so it can get away from the turtles?
Do I need to pack up and find a new spot?
Wait till Winter?

How big of catfish are you targeting, what size bluegill, etc? If you're not going after goliaths then you can use a smaller hook so that its easier on your bait. Make sure to hook it properly through the back. Give it enough line away from the weight to swim around a little, and be conscious of moving water if in a river/creek or the waves in a windy lake potentially bashing it. If you're catching turtles you might not be deep enough either, since its still September and not as many sizable cats will be shallow. Bait should be pretty much as big as possible and still fit into your target fishes mouth. Bullheads under 7 inches are also an option, those things refuse to die on a hook and will still get eaten up by blues and channels. I've personally never had a turtle except for soft shells go after my live bait so I'm inclined to think your gill is either dying or struggling to stay alive.

Eric

I am using big baits. Thinking this would eliminate the turtle factor, but you may be right about the room to swim. Right now I am fishing large ponds/small lakes. Lost of grass in hopes of catching a decent cat or bass. I may need to consider another location of the lake that is deeper and less grass.

Gotcha, not wanting to catch turtles or bullheads with cut bait...

If you're fishing "in" the grass your gill might be getting caught and choked out in it because it either gets dragged into it by the weight or the line catches in the grass... Find where the weedline is and find where it comes to a point and cast to the outside edge. Any sort of cover like a sunken branch where a cat can find shade is a good spot for live bait too.

Eric

I can't count the number of times I've reeled in a dead minnow with the innards missing. I always thought the culprit was either soft-shells, or gar. Seems like I encounter this problem when the cats are flat not biting. When the catfish are hitting, I don't have much problem with bait stealers. You might try a different spot, or fishing at a different time.