Dolphins have been observed creating and playing with intricate bubble rings. Learn all about bubble ring play in dolphins in this week’s episode.
Many animals, especially young animals, spend a lot of time playing. This is especially true of large mammals that we often rank high on the intelligence scale; dogs, apes, humans –and, of course, dolphins. One variety of play tends to stand out as particularly complex; playing with objects. Dolphins, like dogs, will often use objects that they find in their environment for games like keep-away or tug of war. This includes seaweed and ocean debris, but also living ‘objects’ like marine turtles and octopi. Octopi, as you can imagine, are probably not too thrilled at the idea of being intimately involved in a dolphin tug of war, but I’ve seen it happen – unfortunately, it usually does not end well for the octopus involved.
Perhaps one of the most fascinating forms of play in dolphins was described in a 1996 issue of Scientific American by Ken Marten and colleagues at Project Delphis. They describe the behavior of young bottlenose dolphins creating bubble rings. Dolphins can produce all sorts of bubbles by releasing air from their blowholes under water. They create large bubble clouds, bubble streams, and even individual bubbles. Many of these serve as visual displays, a kind of communication signal. But the bubble rings Marten observed were special. In order to make these bubbles, the dolphins first churned up the water using their fins, creating a kind of swirling vortex. They then blew a bubble into the swirl, causing a hole to appear in the vortex. This created a stable ring shape that dolphins then manipulated in a variety of ways. Dolphins can create a ring that either moves in a horizontal or vertical direction or that appear to hover in once place. By churning up the water around the ring, a dolphin can manipulate the direction of the ring, flip it around, and even change its direction of travel. They have also been observed creating a second or third ring and joining the rings together.
The fact that this kind of play is produced with apparent foresight is rather astonishing. To manipulate the rings, a dolphin must plan her timing perfectly, and position herself in just the right spot. This kind of planning requires a fairly large amount of complex cognition in order to execute the series of behaviors required to manipulate the rings properly. In a comprehensive study on bubble ring production, Brenda McCowan and colleagues found that dolphins not only engage in these kinds of behaviors, but exhibited behavior suggesting they were keenly aware of the physical properties and behavior of the rings they produce. For example, dolphins will blow a second bubble ring and attempt to join it together with the first, but this will only work if the first bubble ring is well formed – that is, if it is smooth and round. If it is of poor quality, the two rings generally don’t join up well. The researchers found that dolphins will only produce a second bubble ring if they judge the quality of their first bubble ring to be good enough, otherwise they won’t bother. In this sense, they appear to actively monitor the quality of their rings, and to adjust their behavior according – a very complex kind of play indeed. There is even some evidence that dolphins will teach each other the skills required to play with bubble rings.
There are a variety of excellent resources on the web documenting and discussing bubble ring play in dolphins. To learn more about dolphin bubble rings, and to watch a video of a beluga whale creating a bubble ring, visit the dolphin pod website.
Dr. Ken Marten discusses dolphin bubble rings
(Dutch voice-over – you can hear Dr. Marten discuss bubble rings ~ 4 min into video)
More about bubble rings: Bubble Rings