Page 47 - Spring2019

Heptuna’s Basic Training
When Heptuna first joined the Navy, he went through the standard “basic training” procedures used for all Navy dol- phins. Exceptionally skilled trainers provided conditioning and acclimation to the Hawaii environment. Heptuna was a fast learner and quickly picked up a fundamental under- standing of visual (hand signals) and tonal stimuli needed for specific experiments.
One of the things that made Heptuna such a great experi- mental animal, leading to his involvement in so many ex- periments, was that he had a great memory of past experi- mental procedures and response paradigms. Heptuna also had a willingness to work with the experimenter to figure out what he was supposed to learn. Sometimes, for the less expe- rienced investigator, Heptuna would teach the experimenter.
Heptuna’s First Study
After initial training, Heptuna’s first research project was a study of sound source localization by University of Hawaii zoology graduate student, Donna McDonald (later Donna McDonald Renaud;1 Figure 2). Donna’s mentor, Dr. Arthur Popper, had not worked with dolphins, but he knew a few people at the NUC. He reached out to that group, and they were intrigued by the idea of working with a doctoral stu- dent. Donna, Art, and the leadership at the NUC decided that a sound localization study would be of greatest interest because no one had asked if and how well dolphins could localize sound (though it was assumed that they could deter- mine the location of the sound source).
Donna was trained by Ralph Penner, the extraordinary head trainer at the NUC and Heptuna’s first trainer. Donna and Ralph first trained Heptuna to swim to a bite bar (a task he would use in many subsequent studies; Figure 2), hold his head still, and listen for a sound that came from distant underwater speakers. Heptuna had to discriminate sounds coming from his right or left as the speakers were moved closer together. The goal was to determine the minimal angle between the speakers that could be discriminated (MAA). As soon as Heptuna determined the position of the source, he would swim to a response point on the left or right (Figure 3). If he was correct, Donna would reward him with food.
Heptuna quickly picked up the task and for more than two years gave Donna interesting data that examined sound lo- calization abilities for different frequencies and sounds (Re-
1 This article is dedicated to the memory of Dr. Donna McDonald Renaud (1944-1991), the first investigator to do research with Heptuna.
Figure 2. Heptuna’s pen for training in Kaneohe Bay, Hawaii. The speakers for the sound localization are at the far bars and the bite bar to which Heptuna held on is in the center of the first cross bar. Equip- ment is in the shack, and Donna Renaud is seen preparing to throw food to Heptuna. Inset: picture of Donna from 1980, kindly provided by her husband Maurice. Donna passed away in 1991.
Figure 3. Heptuna hitting the response paddle, ca. 1972. These were the days before many electronics, so the trainer had to see what the animal did and then reward him immediately.
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