An alternative to bird netting: in a ratio of four packets per gallon of water, take grape and only grape unsweetened Kool-aid and spray it in your fruit trees. You don’t need to do a lot. It repels birds by irritating their lungs so they stay away, and by my observations it clearly repels squirrels as well. Raccoons and possums, apparently not so much, though, so this year I bought some Erva bunny cages and put them around the bases of several of my fruit trees–but not all, because they were expensive and I wasn’t sure how much this might work.
For a little more information on the Kool-aid, see here: Grape Koolaid to repel birds
The result is, one peach tree that didn’t get an Erva cage was stripped bare the moment the fruit started to turn pinkish, while right next to it, a peach tree that did remained and still remains loaded with fruit. Note that both are along the fence line and easily accessed by squirrels if they wanted to. This is the first year they didn’t want to. (Note that there may be fewer of them this year due to the extreme drought in California, although they’re definitely still out there.) I’ve watched them run down the fenceline and then exit stage left leaping away from the Kool-aid trees and into the neighbor’s fruitless one on the other side.
I didn’t anchor the cages down, even though they came with stakes: I wanted them to jostle a little to spook anything that tried to climb over them. Clearly, that worked! I planted my trees seven or eight years ago and this is the first year I’ve had full trees of ripening fruit left untouched and the first year we got to pick our sweet cherries as well as the sour ones, which birds like but critters don’t.
Another factor may be that squirrels don’t seem to like a tree with a cage at the bottom barring their way from running down it and away, so there’s now one around my fig tree as well.
Good luck!