Turkeys.
We are, and have been, over run with wild turkeys for years; they can only eat so many; also they can die from eating too many, as it plugs them up.
Last two years were declared ‘ag emergencies’, which allowed the use of normally disallowed pesticides on a large scale.
I did spread a grasshopper disease spore last year, but killing on an acre surrounded by thousands of (government) acres of uncontrolled breeding grounds doesn’t make a dent.