Mourning doves are supposed to be ground feeders, but that didn't stop this one. Note that the weight dependent spring mounting for the perch is partially closing the opening to the seed making it more difficult for the bird to reach it.

The squirrels have learned to sit on the deck railing and pull the feeder towards them so they don't have to lean on the spring mounted perch. (Note...the spring is still closing the opening a bit!)