Black Birds and a Cherry Tree

We have a cherry tree in our back yard that has been my joy for the past few months. It had been growing so many cherries that some of the limbs were even starting to bend down from the extra weight. The tree is probably about 30 feet high and we expected to be eating cherries clear up until august off the tree.
I had gone out and picked about 350 cherries one evening that weren't sweet enough yet but they were good enough to eat. I made up my mind that every week I would go out and pick a couple hundred as a nice sunday night treat.
We got home from church and went out in the backyard to eat and relax in the shade.
I saw the tree and few birds in it but couldn't figure out what was wrong, until my wife says go ahead count all teh cherried the birds left us. I tried looking and I couldn't see anything I thought this was some sick joke because the day before they were just about the perfect color. I came up and sure enough the birds had eaten at least 10,000 cherries my rough but conservative estimate of what we planned to have. I was sad to say the least so if no one gets homemade cherry jam for Christmas you will now know why.