This report is a brief initial look at this problem. It presents data 

 on underwater noise measured in the vicinity of OCS oil and gas platforms, 

 discusses propagation of this sound in the ocean, and considers potential 

 interaction of the sounds with certain marine aniinals. Major attention is 

 given to those species which are most likely to be sensitive to sound. The 

 Cetacea (whales, dolphins, and porpoises) have been particularly selected for 

 this analysis because of their known uses of, and observed sensitivity to, 

 sound (Herman, 1980). 



The ultimate objective of this project is to describe the behavior of 

 the various species of marine animals in response to the various noises 

 produced by the OCS oil and gas operations. This is a very difficult goal, 

 one which may be attainable with confidence only after comprehensive 

 observations of behavior of many animals in the presence of many types and 

 levels of noise. Such observations would need to be made for long periods of 

 time in order to determine whether observed changes in behavior were 

 temporary, and whether the animals readily adapt to the continuation of the 

 noise with no sustained adverse effects. Furthermore, to predict a 

 substantial adverse effect on a species, one must determine whether such 

 effect is deleterious to the existence of the species or to its ecological 

 interactions. Even a sustained effect of the noise, such as denying a favored 

 habitat, might simply displace the habitat by a mile or two, with no serious 

 adverse consequences. 



G-6 



