Most of my cherries froze just after they formed from the blossoms. Now the birds are eating what is left. I don't want to kill them just to keep them away from the cherries. Covering the tree with netting is the usual best answer. And it is not that good an answer.
Large trees are hard to cover.
If the netting doesn't reach the ground on all sides of the tree, you will find some very fat birds under the net enjoying your precious cherries. If there are cherries near the netting so that the birds can reach them from the outside, the birds will perch on the netting and peck all the cherries they can reach. Other gardeners use scare tactics. Most birds are easily startled and that is a characteristic we can use to our advantage. First, the rubber snakes and plastic owls don't effectively startle the offending birds.