Abstract: A bird anti-perching device for preventing birds and other animals from perching, nesting or crossing on billboards and other structures such as utility lines, branches, ledges, roof tops and overhangs. In a preferred embodiment, the device has a plurality of rotatable rings strung consecutively on a cable supported above the top frame member of a billboard. The cable is supported above the top frame member by two support arms placed at opposite ends of the billboard. The support arms incorporate a tightening means for making adjustments in the height and rigidity of the cable.