Squirrels eat just about everything except my citrus (grapefruits, lemons, oranges, mandarins are ignored). One winter 4 or 5 years ago they ravaged my meiwa kumquat tree but that has not been repeated since (that was a low production year for my pecans, and acorns, so they must have gotten desperate). Curiously they left my carambola alone (it froze last year so I don't have it anymore) and it was very productive. Squirrels will eat my peaches, persimmons and pomegranates when they are still small and hard. They are murder on my figs and clean up what the birds leave.
Best option is to trap, shoot or poison but poison has collateral damage I do not like to consider.