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CROSS-REFERENCE TO RELATED APPLICATION 
       [0001]    Not Applicable 
       FEDERALLY SPONSORED RESEARCH 
       [0002]    Not Applicable 
       SEQUENCE LISTING OR PROGRAM 
       [0003]    Not Applicable 
       STATEMENT REGARDING COPYRIGHTED MATERIAL 
       [0004]    Portions of the disclosure of this patent document contain material that is subject to copyright protection. The copyright owner has no objection to the facsimile reproduction by anyone of the patent document or the patent disclosure as it appears in the Patent and Trademark Office file or records, but otherwise reserves all copyright rights whatsoever. 
       BACKGROUND 
       [0005]    The present invention generally relates to bird repellent systems. Bird repellant articles, devices, and systems are known in the art. Commonly known devices are installed on towers, areas with a large pedestrian population, or other buildings with signs. For example, U.S. Pat. No. 6,622,436 to Kretsch discloses a method of deterring waterfowl trespassing with a barrier consisting in its simplest form of a pair of lines suspended above a property surface, with one line at 3 to 10 inches high, a second line at 8 to 30 inches high, and a separation between the lines of at least 5 inches. The lines are suspended by means of an array of posts. Preferably, a dispenser for feeding a line from a spool and also for retracting the line is mounted on one of the posts. The barrier is optimally removable, including means for retracting the line and for conveniently removing the posts from receptacles in the property surface. While Kretsch seeks to deter trespass by geese on foot, it is not designed to stop birds from roosting on structures above ground. 
         [0006]    Also known are wires and metallic spikes placed atop structures such as shopping centers and building signs to stop pigeons from nesting, and to prevent pigeon droppings. For example, U.S. Pat. No. 4,937,988 to Gratton discloses a barrier for preventing pigeons from landing on a balcony rail comprising a pair of support brackets adapted for flush mounting to opposite ends of the balcony rail, and a plurality of monofilament wires secured between the pair of support brackets. Gratton is specifically adapted for balcony railings and is designed to serve as a more permanent barrier that cannot easily be removed if maintenance or construction activities were to take place. 
         [0007]    Both Gratton and Kretsch are also insufficient in that they constitute “fences” only, which may not deter birds from landing behind the “fences” (e.g., inside a large balcony). 
         [0008]    There is a special need for deterring birds other than just pigeons from roosting on other types of structures, and for reasons other than to prevent pigeon droppings. For example, birds that nest on transmission towers obstruct workers from conducting maintenance and construction activities on the towers, causing costly delays. Birds also roost on power poles and interfere with transmission lines, causing electrical damage and outages that interfere with homes and businesses. Furthermore, airport towers require bird repellents to deter birds from landing and to thereby avoid aircraft collisions. At the same time, these structures require a non-metallic repellent that does not interfere with transmissions, and since the type of bird that interferes with a tower can vary by location, the bird barrier must be adjustable to target different kinds of birds, and not just pigeons and geese. Because some birds are federally protected, it is necessary to create a barrier that only repels birds without injuring them, and since it is possible for birds to land behind a fence, the barrier must be sufficient to prevent this from happening. 
         [0009]    The problem of deterring birds from roosting on transmission towers, including television towers, radio towers, cell phone and communication towers, electrical towers, electrical power poles, FAA and airport communication and antenna towers, radar and weather platforms, airport runway signs and other airfield installations, is solved by a non-metallic barrier comprising shaft bases with shafts that can be easily removed by workers when performing maintenance or construction activities, and that comprise bores through the shaft which cords can be woven into various grid patterns to deter birds of various sizes, including crows, ospreys, harriers, hawks, eagles, falcons, owls, herons, egrets, bitterns, vultures, California condors, Ibises, pelicans, cormorants, and gulls, from landing on top of structures. 
       SUMMARY 
       [0010]    The present invention comprises a non-metallic bird repellent system. The system comprises a shaft having a longitudinal round surface, wherein at least one bore disposed latitudinal on the round surface of the shaft is utilized for creating multiple links and grid patterns between the shafts. 
         [0011]    A shaft base having an arced horizontal member comprises a tubular projection from the outer surface and perpendicular to the horizontal member, wherein the tubular projection comprises a tubular recess disposed along the central longitudinal axis of the tubular projection and is in continuous contact with the horizontal member along the entire length of the tubular projection for holding the shaft upright. 
         [0012]    The shaft inserts into the tubular recess of the shaft base and is held upright, wherein the shaft base is fastened to a transmission tower by means of a cable tie. 
         [0013]    Links between the installed shaft and shaft base with cords comprise a mesh or grid pattern wherein the cord link system comprises a cord strung through all the bores on the shafts and securely knotted. This cord link system further comprises a visual mesh or grid pattern between multiple shafts. 
     
    
     
       BRIEF DESCRIPTION OF THE FIGURES 
         [0014]      FIG. 1   a  shows a base and shortened shaft of the present invention. 
           [0015]      FIG. 1   b  shows a base, sleeve, and shortened shaft of the present invention. 
           [0016]      FIG. 2  is a cut away view of the present invention showing alternate installation locations. 
           [0017]      FIG. 3   a - 3   c  shows various shaft embodiments in perspective view of the present invention. 
           [0018]      FIG. 4  shows a close up view of the invention from an angle. 
           [0019]      FIG. 5  shows an example of a grid pattern that can be formed by linking shafts with a cord. 
           [0020]      FIG. 6   a  is a perspective view of the present invention installed on a electrical pole. 
           [0021]      FIG. 6   b  is a perspective view of the shaft base of the present invention having two bores. 
       
    
    
     DETAILED DESCRIPTION 
       [0022]    Referring to  FIG. 1 , a bird repellent system is shown and described. In the preferred embodiment, the system  100  comprises a shaft  10  having a longitudinal round surface, wherein at least one bore  12  disposed latitudinal on the round surface of the shaft  10  is utilized for creating multiple links between shafts  10 . 
         [0023]    Still referring to  FIG. 1 , a shaft base  16  having an arced horizontal member comprising a tubular projection  14  from the outer surface and perpendicular to the horizontal member, wherein the tubular projection  14  comprises a tubular recess disposed along the central longitudinal axis of the tubular projection  14  and is in continuous contact with the horizontal member of the shaft base  16  along the entire length of the tubular projection  14  for holding the shaft  14  upright. 
         [0024]    An alternate embodiment of the invention comprises a two piece tubular projection  14  in which the tubular projection comprises another piece inserted into the tubular projection, called the sleeve  14   a,  which lengthens the tubular projection  14  thereby adding support for the shaft  10 . 
         [0025]    Still referring to  FIG. 1  of the system  100 , an alternate embodiment of the invention comprises a tubular projection  14  with a bore  12  that corresponds to the bore  12  of the shaft  14  when the shaft  14  is inserted into the tubular projection  14 . A cord can be inserted through the bore of the tubular projection and the bore of the shaft to secure the shaft  14  and shaft base  16  to a pole or horizontal platform. 
         [0026]    Referring to  FIG. 2  of the system  100 , the shaft  10  inserts into the tubular recess  15  of the shaft base  16  and is held upright. The shaft base  16  may be installed on tower  30  structures that utilize circular or square tubing  30 . 
         [0027]    Referring to  FIG. 3   a - 3   b  of the system  100 , alternate embodiments of shaft  10  tips are shown. The first tip  10   a  comprises a smooth cone shaped surface. The second tip  10   b  comprises an angled surface. The third tip  10   c  comprises a flat latitudinal surface. 
         [0028]    Referring to  FIG. 4  of the system  100 , the shaft base  16  is fastened to a a communication and/or transmission tower  30  of interest by means of a cable tie  17 . 
         [0029]    Still referring now to  FIGS. 4 and 5  of the system  100 , links between installed shafts  10  with cords  20  comprise a mesh  200  or grid pattern wherein the cord  20  link system  200  comprises a cord  20  strung through all the bores  12  on the shafts  10  and securely fastened with a knot  17   a.    
         [0030]    Referring to  FIG. 5  of the system  100 , one example of a mesh  200  or grid pattern is shown. The mesh or grid pattern can be used not only to create fencing to block off access from the sides, but also to cover the tops of structures to block off access from above. 
         [0031]    Referring to  FIGS. 6   a  and  6   b  of the system  100 , an alternative embodiment of the shaft base  16  comprises two bores  12   a  on the horizontal member through which nails or screws may be inserted to fasten the shaft member to a wooden horizontal surface such as an electrical pole  300 . 
         [0032]    All features disclosed in this specification, including any accompanying claims, abstract, and drawings, may be replaced by alternative features serving the same, equivalent or similar purpose, unless expressly stated otherwise. Thus, unless expressly stated otherwise, each feature disclosed is one example only of a generic series of equivalent or similar features. 
         [0033]    Any element in a claim that does not explicitly state “means for” performing a specified function, or “step for” performing a specific function, is not to be interpreted as a “means” or “step” clause as specified in 35 U.S.C. §112, paragraph 6. In particular, the use of “step of” in the claims herein is not intended to invoke the provisions of 35 U.S.C. §112, paragraph 6. 
         [0034]    Although preferred embodiments of the present invention have been shown and described, various modifications and substitutions may be made thereto without departing from the spirit and scope of the invention. Accordingly, it is to be understood that the present invention has been described by way of illustration and not limitation.

Summary:
A bird repellent system comprising a round shaft and shaft base installation securely fastened to a tower, wherein the shaft is inserted perpendicularly into the tubular recess of the shaft base and held upright. The shaft comprises through which links can be formed to create a mesh or grid pattern to repel birds from landing or roosting on top of a tower structure.