This is what my father did
He bought a bunch of pop gun ammo, then using a hammer, laid out a couple on the sidewalk and smashed a few. This went on every evening when it was loudest, for about a week or two. Eventually they stopped dropping by our tree.
Then next year, we had fewer birds. I guess the word got around not to stop off at our residence. We only used the pop caps a few times and it was all good after that.