Nest box for birds such as woodpeckers, has groove which is formed in lower portion of air hole that is formed in front wall of casing

摘要

The nest box (10) has a casing containing a front wall (30) in air hole (20) is formed. A groove (24) is formed in the lower portion (22) of the air hole. The depth of the groove is set to 5-10 mm. The front shoulder (26) and rear shoulder (28) are formed near the groove of the air hole. An independent claim is included for method for manufacturing nest box.