Wildlife Damage Management, Internet Center for


Date of this Version

September 1970


In 1969 and 1970, with cooperation with Mr. Bill Shake of the U.S. Fish and Wildlife Service, attempts were made to assay the actual dollar damage done to a blueberry planting and what affect the carbide gun, BioSonics taped scare call and Av-Alarm electric sound device had on control of bird damage. Both the BioSonic and Av-Alarm units were battery operated and photo cell controlled to turn on and off automatically. These features are of great importance to the blueberry grower who is faced with a shortage of labor and increasing labor cost. It was necessary to select fields several miles apart so that each could be evaluated on its own merits. However, we soon learned the bird population varied from field to field as well as the species. Also, the tagging and evaluation of fruit for damage was very unsuccessful. The battery powered equipment was not fully evaluated because at some time during the studies one or the other piece of equipment was stolen from the field. While the equipment was designed to rock the birds, it probably wound up at a rock festival! This year, 80 Av-Alarm units have been sold in Michigan and northern Indiana. Some blueberry growers have claimed very good bird control, especially of the flocking starlings. The growers reporting the best control also spend the most time varying the sounds produced by the device or use decoy traps, carbide guns or shot¬guns in addition. It appears to me that each blueberry farm has a particular bird problem and that each farmer needs to spend some time to determine what his prob¬lem is and how best to control it. The blueberry grower is concerned with the actual fruit or dollar loss. The Michigan Blueberry Growers Association is the growers' Marketing cooperative. The fruit sold by the Association must be free from insects, pesticides, foreign material, bacteria and within limits on mold. This year, research work indicated that bird pecked berries may actually have more mold; and since birds are known to carry bacteria such as salmonella, we are concerned that they may also spread this or some other bacteria. More research is needed to determine this potential hazard.