Hi There, Live in southern California. Purchased a home with a large orange tree in the backyard. Do not know what kind of oranges they are. During the past month, the oranges have a large 2 inch hole eaten out of the skin and the orange has been eaten away at. We are not talking 1 or 2 oranges. More like 20 - 30. Does anyone have ideas? There is no noticeable insects on the tree. Any help would be obliged.
Most likely birds. Orioles certainly like oranges, people often put half-oranges out to attract them.
Rats are probably the culprits. Souther CA has a problem with roof rats as well which will climb into trees.
My first thought was rats. I was going to set up a trap and peanut butter as we have caught the odd one by our garbage cans. I assume since we have so many oranges exposed it is the culprit for the mass amount of flies in our backyard! I will try some traps tonight and see what happens. Keep posted!