THE NAVY OCEAN SCIENCE PROGRAM 



39 



Section of six-inch pipe formerly located over the boiler of a Navy ship. 

 The pipe is almost closed by fouUng marine growth. 



A project of long duration is the study of false acoustic targets 

 in the sea caused by large mammals and by schools offish, which 

 return echoes and otherwise appear similar to ocean-bottom 

 and military targets. This work involves recording echoes ob- 

 tained under various environmental and experimental condi- 

 tions, analyzing them in frequency, amplitude, and time, and 

 developing conclusions which can be used by fleet personnel 

 dxiring operations or equipment development. Closely related to 

 these studies is the collection of accurate information, including 

 recordings of the sounds produced by marine animals, the 

 geographical and seasonal distribution of the sound producers, 

 and the habits of the animals which are significantly related to 

 soimd production. The organisms range from whales and por- 

 poises through numerous fish to invertebrates, including notably 

 snapping shrimp. 



A newly constructed audio-video laboratory has permitted 

 investigations on biological acoustics. From these studies it has 

 been shown that sharks can detect and respond to a wide range 

 of sounds, and that they are attracted rapidly to a series of sonic 

 pulses. An observation chamber that can follow a school of 



267-116 O - 67 



