I have built a veritable bird house estate or some 6 boxes, around my allotment, and the only residents for the past three years have been wasps ! As these much maligned creatures are more beneficial to the gardening than some ungrateful birds, they are now most welcome !
I am gunna re-site the boxes this January, and hope a hoopoe might lose it's way and reside temporarily ! The ONLY successful nesting was in a joke box, and a wren made it a home for one band of hooligans