Most of us have turtles in our ponds, right?

Turtles love fish food, in my ponds. When they get too numerous and too bold at the fish feeders, one well placed explosion from a 12 guage shotgun and the turtles do not come back to the feeders for a long time.

Now these turtles that don't come back haven't actually been abused directly by the blast...but they have observed the result. Without doubt, the very next feeding following such an exercise in behavior modification is met with turtles that only observe the feeders from a distance but do not partake in the bounty thereof.....but maybe my turtles are different or follow a different behavior model than turtles elsewhere?

I might add, the turtles in question have far more than 500 positive reinforcements under their shell, but one well directed blast seems to undo that reinforcement instantly.