Setting sticky traps is a good way to ID fruit pests. If you're seeing such a damage, you can wrap a ball with plastic wrap and slather products like Tanglefoot which is sold for the purpose, or petroleum jelly or other unscented sticky product. I don't have the kind of fruits you have, but for apples, you're supposed to hang green small balls for pests attacking green apples and red balls for pests attacking red apples, so similar technique will probably apply.
I honestly haven't used the product enough to form an opinion, but I started to use, and am going to use again this year, Surround -- superfine milled kaolin clay -- in liquid suspension. The white clay coating is supposed to visually and [the smell -- what's the word for that?] - ly confuse them, and physically block them as well.