Changing Behaviors Tom and Misha’s situation is extreme but not unique. Approximately 2,900 captive dolphins live in almost 300 research aquariums, theme parks, and tourist attractions worldwide. Most were captured from the wild. Wild dolphins lead unpredictable, fast-


paced lives. Survival requires changing their behavior to match their circumstances. In Australia, for example, dolphins have learned to skim through shallow water across the sand to snatch up fleeing prey. Elsewhere, dolphins form teams to herd fish into a tightly packed ball or stir up curtains of mud to confuse their prey. Some team members maintain the corral of fish while others dart in to feed, taking turns until every dolphin is full. In contrast, captive dolphins rely on humans


for food. Trainers provide fish when dolphins follow commands and sometimes withhold food to punish bad behavior. Dolphins are intensely aware of such power


dynamics. In the wild, they have complex social structures. Teir naturally occurring social behavior may explain why dolphins have such big brains—second only to humans in terms of body weight. Wild dolphins spend most of their time with a few close companions. Tese core groups merge to form secondary alliances, which blend into pods of up to 300 individuals. Pods are fluid and shiſt depending on which other dolphins are nearby.


Social Bonds Wild dolphins spend one-third of their time maintaining relationships. One bonding method is the “signature whistle,” a unique set of clicks each dolphin uses to identify itself. When meeting, they exchange these whistles the way humans exchange names. Dolphins learn the whistles of pod members and appear to remember them, even if they haven’t seen a pod member in years. Social bonds are also important for dolphin


survival in captivity. When Tom developed a dangerous blood infection, Misha brought him fish to eat. Misha also helped Tom to the surface and held him up when he was too weak to breathe on his own.


JANUARY–FEBRUARY 2016 7


Unlike the more independent Misha, Tom


sought contact with people. He swam up to greet anyone who approached the pen. Many captive dolphins seem to enjoy such social encounters with humans. Some dolphins form close bonds with specific human trainers, preferring them to other trainers. Bonding with humans is possible because


captive dolphins learn to alter their existing language skills to communicate with humans. When trainers tried to teach Misha to present his fluke, or tail, for a blood test, the dolphin swam to the center of the pool and waved his tail in the air, clearly saying, “You can look, but you can’t touch.” Te dolphin understood the command and then gave his response.


Understanding Humans Dolphins soon learn that hand gestures and body movements have meanings. Tey also understand human words, recognizing that certain words refer to actions or objects. Even when obeying instructions, dolphins


sometimes think for themselves and improvise. Hector and Han, two dolphins at a research aquarium in Honduras, have learned how to “innovate in tandem.” When a trainer gives the command to do so, Hector and Han swim below the surface and exchange clicks and whistles. Ten they spring into action, performing a move they haven’t already done that day in perfect sync. Perhaps one dolphin copies the other so quickly that human eyes can’t see the lag time. But it’s more likely Hector and Han are working out a plan, especially since they oſten perform moves their trainers haven’t taught them.


Dolphins live in social groups that hunt and play together.


Page 1  |  Page 2  |  Page 3  |  Page 4  |  Page 5  |  Page 6  |  Page 7  |  Page 8  |  Page 9  |  Page 10  |  Page 11  |  Page 12  |  Page 13  |  Page 14  |  Page 15  |  Page 16  |  Page 17  |  Page 18  |  Page 19  |  Page 20  |  Page 21  |  Page 22  |  Page 23  |  Page 24