Humpback whales migrate to Hawaiian waters each winter to nurse and mate, but they sometimes interact with other species and the accompanying video features the first recorded examples of the gregarious cetaceans lifting bottlenose dolphins out of the water with their heads in what seems a game for both animals (the first images showing this phenomenon appear 30 seconds into the production).


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Photographs of these peculiar events -- one occurred near Kauai, the other near Maui -- are featured in the video, which was posted recently to the American Museum of Natural History website as part of its Science Bulletins program.

"The two species seemed to cooperate in the activity, and neither displayed signs of aggression or distress," the website describes. "Whales and dolphins in Hawaiian waters often interact, but playful social activity such as this is extremely rare between species."

During the Kauai episode, a bottlenose dolphin was lifted gently out of the water by a humpback whale, and slid tail-first down the whale's head and back into the water.

During the Maui encounter, scientists watched and photographed a humpback whale and bottlenose dolphin performing the same routine six times, with the dolphin sliding gently off the whale head after each "ride."

It may not be everyone's idea of fun, but it sure is cute.