Abstract: A purple martin birdhouse mounted on a receiver that is adapted to be attached to a non-rotatable telescoping pole, the receiver and the sections of the telescoping pole having a bore of cross section the shape of a convex polygon. The shape of the receiver and the telescoping pole prevent relative rotation when the birdhouse is mounted on the pole and lowered for a nest check. A resiliently biased pin connects the receiver to the pole in only one orientation, preventing incorrect polarization of the house when it is reinstalled on the pole at the beginning of a season.