The Natural Bird Guardian Birdhouse Protector
Bird Guardian was designed for all cavity-nesting backyard birds. Patented, tested and approved by naturalists, this one-of-a-kind product protects nesting birds from squirrels, cats and other predators. The Bird Guardian is easily attached to the front of the nest box. This well engineered product will prevent predators from bending their arms to reach the resident birds. Crows, bluejays, grackles and others have no room to get their shoulders in your nest box! The Bird Guardian has a patented tail-brace that allows the bird easy access.
Available from Duncraft Bird Watcher Supply