Pygmy killer whales are found in tropical and subtropical waters around the world.
Okinawa Churaumi Aquarium is the only facility in Japan rearing a pygmy killer whale. Wild pygmy killer whales are aggressive toward other dolphins, and this is the same in a captive environment. The pygmy killer whale showed frequent aggression toward other dolphins in the tank or the trainers. Social behaviors, such as playing and swimming with others, were also seen less. To encourage more social behavior and reduce aggression, Okinawa Churaumi Aquarium used behavior modification in a similar way to human psychotherapy. This led to an increase in social behavior and significantly reduced aggression. This was done by repeatedly providing a reward of toys, but only when the dolphin showed no signs of aggression. Now, the pygmy killer whale can be raised with other dolphins, and participate in experience programs.

Authors

Sayaka Seto, Suguru Higa, Isao Kawazu

Title

Suppression of aggressive behavior in a captive pygmy killer whale using behavior modification

Journal

Journal of Japanese Association of Zoos and Aquariums (in Japanese with English abstract)