FACTORS TO CONSIDER WHEN SELECTING AND EVALUATING DEVICES 



Several factors must be considered when devices are being selected for 

 use, either during experiments or during spills. 



1. Oil spills are very dynamic phenomena. The oil moves with 

 the winds and currents; the initial slick spreads out and 

 breaks up into smaller slicks; the oil weathers and the 

 composition of the oil changes. Consequently, in most cases, 

 deterrent methods will have to be mobile in order to stay 

 with the oil. Only when the oil is diverted or drifts into 

 clam water areas (e.g., bays) will stationary deterrent 

 methods become useful. 



2. Birds can become oiled either by swimming into the oil 

 before they are aware of it or, in some cases, by landing 

 in it. Therefore, devices will have to be evaluated for 

 effectiveness against both flying birds and swimming birds. 



3. Birds appear to be most susceptible to contacting oil 

 during the hours of darkness, and this is also the time 

 when there is the least amount of activity associated with 

 cleanup operations. Effective deterrents must, therefore, 

 be functional during the dark as well as during daylight 

 hours. 



4. Oil spills often cover extensive areas; consequently, 

 deterrents must have a large radius of effect in order to 

 be of practical value. 



5. Birds will habituate to deterrent devices. This is an 

 important aspect that should be considered during experimental 

 evaluation of deterrents. 



6. The difficulty in deterring birds from a given area varies 

 according to the attractiveness of the area to the birds. 

 For example, if oil drifts toward a bird sanctuary, it may 



be extremely difficult to frighten the birds from the sanctuary 

 (other examples include feeding areas and breeding bird 

 colonies). 



7. The responses of different species to a deterrent may not be 

 identical. Diving birds such as loons, grebes, and alcids 

 tend to dive in response to danger rather than fly away, 



and this behavior may increase the chances that they will 

 encounter oil. The best devices for diving birds, then, 

 will be ones that cause them to take flight. Other birds 

 such as dabbling ducks and gulls generally take flight in 

 response to danger. It must be remembered, therefore, that 

 advice which is useful for one species of bird may not 

 be useful against another species. 



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