After establishing the basic parameters of the Sumo Birdhouse, several concepts are considered.

No. 1 Birdhouse with shock absorbers. Recoil led to unacceptable bird head injuries.

No. 2 Birdfeed grate with recycling hose. Grate trapped recyling hose, but vacuum sucked in Sumo Birds.

No. 3 Birdhouse with sloped interior dining well. Interior well eliminates feed spillage. Cork over plywood floor reduces stress from impact shock to an acceptable level.