Have you asked your neighbors who have orchards how they keep the ravens away from their trees? They may have a helpful suggestion.
There is a product called "Tanglefoot" that supposedly keeps birds away from fruiting trees. We haven't tried it.
We use deer netting, doubled over our trees, not so much for birds but for grasshoppers. It would deter birds from landing, I'm sure. It's rather cheap, and you can secure it with common clip clothespins if you need to. Our trees look a little strange, but they aren't getting chewed by 'hoppers!

We have alot too,I saw one year liike 6 came in they each would take a peach,the deer ate all my pears this year,I have kiwi a chipmunk ate all those.

"Have you asked your neighbors who have orchards how they keep the ravens away from their trees? "

They had the guy in the middle plant trees that the birds like better than theirs...........

My FIL made whirly thingamagigs out of aluminum cans. He had pecan trees and hung these in the trees to keep the squirrels away. Worked pretty good. If I remember correctly it took 2 cans to make one. You cut the top out of the cans. This includes the rims. Cut one can in strips down halfway and bend the strips to form a pinwheel effect. punch a hole in the bottom centers of each can and insert the pinwheel can into the the other can. Hang several of these in your tree. The holes are to use for hanging. The wind blows the pinwheels catching the sun on the vanes. It worked for his squirrels. The only advantage I see over the deer netting is you don't have to take them down unless they stop working and then you replace it with a new one. You can't leave deer netting up year round. I'm thinking he an used old wire coathanger as a hanger. Unwind the hanger where it attached to the hook and cut that half off. Insert the bottom thru the cans and turn the end up to keep it from sliding back through. Squeeze the hook of the hanger over the branch to keep it from falling off.