circumstances that could arise, it is difficult to identify precisely those 

 devices most likely to be of use in various types of areas. Consequently, 

 the following discussion is general in nature and is intended only to provide 

 suggestions. 



PONDS AND SMALL LAKES 



It will probably be easier to disperse and deter birds from a small lake 

 or pond than from any of the other types of areas discussed below. It is 

 also probable that oil spilled on small ponds and lakes will seldom be a 

 hazard to large numbers of birds. 



The first objective in all situations should be to disperse immediately 

 all birds that are already in the vicinity of the spill. On a pond or small 

 lake (maximum diameter approximately 1 mile or 1.6 km), a combination of shell 

 crackers and mortars could be used to disperse the birds. A motorboat would 

 be required to reach areas not accessible from shore. On a slightly larger 

 water body, an aircraft might be needed to disperse the birds rapidly. 



Once the birds have been dispersed from the area of the oil spill, deter- 

 rent devices must be set up to prevent birds from returning to the area. 

 Devices that are not species-specific would be most useful. These would include 

 acetylene exploders and revolving or flashing lights. Species-specific methods, 

 such as distress and alarm calls and perhaps "crucified" birds, could be of 

 use if only a small number of different species were of concern in the area. 



MARSHES 



In general, the methods recommended for ponds and small lakes would also 

 be the most applicable methods in marshes. However, birds would be less con- 

 spicuous among the emergent vegetation of marshes than on the open water of 

 ponds and lakes, and would often be less likely to fly. Increased emphasis 

 (relative to ponds and small lakes) on aircraft is recommended for initial 

 dispersal of birds. It should be kept in mind that the marsh vegetation may 

 be sufficiently dense to prevent penetration of the oil, in which case care 

 should be taken not to disturb the birds. 



Development of lure areas in suitable marshes near a contaminated marsh 

 might be useful, but only if there are few other marshes nearby and if few 

 transient birds are moving through the area. If there are other marshes in 

 the area, or if many transients are passing through, the lure area would 

 probably attract more birds into the general areas of the spill and increase 

 rather than decrease mortality. Luring should be attempted only if biologists 

 on the scene have carefully evaluated the probable consequences and concluded 

 that alternate methods are ineffective and that the consequences of luring 

 would definitely be beneficial. 



It will be difficult to prevent birds from attempting to roost in oil- 

 contaminated marshes during the evening, even if they are lured to alternate 

 feeding areas by day. A greater density of pyrotechnics, exploders, and 

 flashing or revolving lights will therefore be required in a marsh than on 

 a pond or small lake. It is suggested that pyrotechnics, exploders, and 

 lights be supplemented with numerous scarecrows and reflectors. 



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