Chapter 45 

 UTILIZATION OF PORPOISES IN THE MAN-IN-THE-SEA PROGRAM 



F. G. Wood, Jr. and Sam H. Ridgway 



U. S. Naval Missile Center 



Point Mugu, California 



BACKGROUND 



The purpose of an ONR funded "Project Arion" being undertaken by the Life Sciences De- 

 partment of the Naval Missile Center is to determine the means by which porpoises can be 

 effectively utilized in scientific experimentation directed toward naval application. 



Sealab II provided an opportunity to test the feasibility of using porpoises in conjunction 

 with the Navy's man-in-the-sea program. With the encouragement and active support of Sea- 

 lab II officials, plans were made for on-site field trials with a porpoise trained to perform tasks 

 appropriate to Sealab n operations. An Atlantic bottlenose porpoise "Tuffy" was an obvious 

 candidate for this due to his participation in a diving physiology study directed by Dr. Sam H. 

 Ridgway. Tuffy had made dives to depths in excess of 300 ft. He had been trained to wear a 

 harness and to home on two different acoustic devices. He was accustomed to working unteth- 

 ered in the open sea. 



PLANNED PROGRAM 



After discussions with Sealab II personnel it was decided that Tuffy's primary task would 

 be to simulate the rescue of a lost aquanaut. Poor visibility was anticipated at the proposed 

 site of Sealab II. A diver has little if any directional hearing capability, and even electronic 

 directional listening devices reportedly are of limited usefulness. 



It was planned that Sealab II aquanauts would be tethered at all times while swimming at 

 ranges beyond the visual range of the habitat. Future operations will require that they range 

 untethered, relying on electronic aids for navigation to return to the habitat. 



Should a failure occur and the diver become disoriented, a strong possibility exists that he 

 will be unable to find his way back to his ocean-floor habitat. 



Future Sealab type experiments will be conducted at increasingly deeper depths, where aid 

 from the surface by surface support swimmers will be extremely difficult. Availability of a 

 trained porpoise to perform certain vital work functions will thus be increased importance as 

 deeper depths are reached, provided the depth limitation of the porpoise is not exceeded. 



As planned, for Sealab II Tuffy would be summoned (by a buzzer, one of the acoustic de- 

 vices to which he had been trained to respond) from the surface to an aquanaut at Sealab 11. 

 That individual would snap a line to one of the rings on the animal's harness, then turn off his 

 buzzer (designated the primary signal). The "lost" aquanaut would then summon the porpoise 

 by turning on his (secondary) buzzer signal. After unsnapping the line that Tuffy had carried 

 to him, he would have a guide back to Sealab 11. 



The "homing" signal to be used by the animal's handler at the surface was the other acous- 

 tic device to which the animal had been trained to respond— a small waterproof strobe light (de- 

 signed as survival gear), the discharge of which produces a broad-band click. Tuffy had reliably 

 come to this signal from distances of over 500 yards in Mugu Lagoon. 



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