US Patent 7721677 Gourd nesting place for purple martins

A plastic artificial gourd for use as a nesting place for purple martins. An outer shell has a neck and an inspection hole and is formed in halves. The front half has an entrance hole for the martins. An inner core is provided with an inspection hole and entrance hole in registry with those in the outer shell. Drainage holes are provided in the bottom of the outer shell and the inner core and the neck is provided with ribs forming an air space when a cap is attached to the neck. The gourd is ventilated though the drainage holes and out the air space under the cap. The inside of the outer shell and inner core may be textured to provide the martins a good footing.