Probably not a good idea. I've read research that says that when a colony of birds have decided a place is worth roosting in, they will stick to it. In fact, when part of the colony is lost, say through intermittent shooting, the remaining will make extra effort to make up the numbers by mating more frequently. The way to get rid of them is to make the whole place untenable, e.g., cutting down the trees (not always the best idea); or as one pest controller suggests, regularly spraying the trees with a grape juice based chemical (which the birds hate).