In two different locations on the coast of Hawaii, scientists have observed unusual interactions between bottlenose dolphins and humpback whales as dolphins rode the heads of whales: the whales lifted the dolphins up and out of the water, and then the dolphins slid back down. In the video published by the American Museum of Natural History below, the two species seemed to cooperate in the activity, and neither displayed signs of aggression or distress. Whales and dolphins in Hawaiian waters often interact, but playful social activity such as this is extremely rare between species.
Why do dolphins ride on whales?
Scientists believe play would be the best explanation. Both dolphins (in this case, bottlenose dolphins) and humpback whales are very intelligent animals can be extremely playful with each other and other species.
One event took place in Kauai, where the dolphins and the whales are swimming close together. A dolphin laid herself across the head of a whale. Then the whale slowly raised the dolphin out of the water until the dolphin slid back down in the water, tail-first.
A few months later, a similar interaction was observed near Maui, also between a bottlenose dolphin and a humpback whale. Again a dolphin laid herself across the head of a whale, and the whale lifted the dolphin six times, the dolphin sliding back into the water after each “ride”.
The slowness of the whale’s movements, the dolphin’s obvious cooperation, and the repeated lifting convinced scientists that this activity was playful rather than aggressive.
These rarely seen examples of spontaneous play hint at the complexity of interspecies relationships in the wild, especially the more intelligent species like dolphins and whales.
Bottlenose dolphins inhabit warm and temperate seas worldwide, being found everywhere except for the Arctic and Antarctic Circle regions.
Numerous investigations of bottlenose dolphin intelligence have been conducted, examining mimicry, use of artificial language, object categorization, and self-recognition. They can use tools (sponging; using marine sponges to forage for food sources they normally could not access), play with each other and other species (as in the video above, as dolphins rode the heads of humpback whales), and transmit cultural knowledge from generation to generation.
Their considerable intelligence has also driven interaction with humans.