Eastern Gray Squirrel

In addition to the birds, chipmunks and rabbits, I get lots of squirrels in my backyard. While I have successfully arranged my bird feeders so that the squirrels cannot feast directly on the seed, there is still plenty of stuff that falls to the ground to keep them content. On the other hand, I need to do something about my poor excuse for a bluebird house. Having the squirrels turn it on its side so that they can use it as a sunbathing spot is a tad annoying.