"Droplet" Birdhouse

Most ordinary birdhouses have a square form-factor; since bird nests are circular there is a lot of wasted space. 

Enter this cozy Droplet birdhouse, plenty of room for a nest, with a drainage hole at the bottom. No perch, and hole measured for small songbirds, especially bluebirds.

Pre-sliced along the central rib, You must use some sort of adhesive to join these two surface. 

I used PCL thermoplastic, you can use epoxy like JB-weld, or cyanoacrylate superglue as well.