A nest exclusion device is releasably attachable to a tower such as a cell tower, such that when installed it deters Osprey and other raptors from nesting on the tower structure, but is easily disengaged to permit worker access to the tower antenna mount structure, and can be easily reassembled. The device includes a center pole that extends upwardly away from the tower. A cap is attached to a top of the center pole, and a plurality of brackets are spaced about a periphery of the antenna mount structure with a maximum spacing between adjacent brackets of 18 inches. A plurality of cable assemblies extend from the cap to the brackets to define a tapering structure, converting the snag-shaped tower to a more conical shape.
