RIVERS 



If oil that had been spilled into a river was contained by booms and/or 

 trapped in a bay, the applicable deterrent techniques would be similar to 

 those useful around ponds and small lakes. However, many devices would be 

 more difficult to deploy. Aircraft would be very useful because of the rapid- 

 ity with which they could be brought into use. Mortars and rockets would 

 be especially useful because of their long range (relative to shell crackers 

 and flares) and the consequent reduction in the need for boats. Boats would 

 be necessary for proper use of shell crackers and Verey flares. 



If the oil is floating downriver, highly mobile techniques would be 

 necessary in order to disperse birds from areas ahead of the advancing oil. 

 The most efficient method would be through use of aircraft and through boat- 

 and/or shore-based crews firing shell crackers, flares, and mortars. It would 

 also be necessary to deter birds from entering the already contaminated area. 

 The difficulty of accomplishing this would be highly dependent on the width 

 of the river, the rate of current flow, and the length of the contaminated 

 section. 



COASTAL AREAS 



Methods applicable in coastal areas would be similar to those applicable 

 on ponds and small lakes. However, because of the less confined nature of 

 coastlines, aircraft would probably be of most value for the initial dispersal 

 of birds. If the section of coastline that was contaminated or about to become 

 contaminated was long, use of aircraft would probably be the only practical 

 dispersal method, and numerous aircraft might be necessary. 



Deterrent methods and devices would need to be deployed along the shore 

 in order to prevent birds from entering the contaminated water. Shell crackers, 

 exploders, lights, reflectors and mortars, together with continued use of 

 aircraft, would be possible approaches. Distress and alarm calls would be 

 useful if calls of the appropriate species exist and are available. The major 

 limiting factor for coastal areas will be the logistical problems of deploying 

 and operating a sufficient number of devices. 



OFFSHORE AREAS 



No tests have been conducted relating to the effectiveness of deterrent 

 methods in offshore situations. It is clear, however, that many of the devices 

 and methods that are useful on and near shore are impractical in offshore 

 areas, at least until the oil can be surrounded by booms. 



The most effective dispersal method offshore would probably be use of 

 aircraft. However, some species of seabirds are more likely to dive than 

 to fly when an aircraft approaches, and some molting species would be unable 

 to fly. Twin-engined aircraft would be necessary for safety, and effective 

 operations would be impossible at night. Searchlights mounted on boats would 

 be useful offshore, but their effectiveness in cases of large spills would 

 be limited. Because of their larger area of coverage, rockets and mortars 

 would probably be more useful than shell crackers and flares, both by day 

 and by night. 



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