A friend of mine currently owns a 3-acre pond that has an overabundance of turtles. He considers them to be a nuisance and would like to eradicate them from his pond and probably a portion of the existing watershed on his property. I explained that although they may be a nuisance removing them could be very time consuming and since his pond seems like a haven for turtles it would make sense that once a void is left from removing the turtles that more will show up. I have a couple of questions.

-A Turtles diet consists of dead fish, invertebrates and plants right? The turtles should not have an effect on the existing living fish population.
-If he does want to remove them what is the best method?
-Once removed should these turtles be transplanted somewhere else? I would think an imbalance would occur in this new area where the turtles were placed. I would hate to see him destroy these creatures though.
-How might you prevent a return of turtles? Is this even possible?

Any thoughts on this topic? Forgive me if this has come up before.