Dolphin Derby

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Today the dolphins came to play
I watched them jump for joy
It seemed just then, they were wise old men
and I, a foolish boy
Wayne Marshal

Greek mythology tells the story of a group of pirates that were thrown into the ocean by the god Dionysus. They were rescued from a watery grave by Poseidon who changed them into dolphins and made them eternal slaves to the human race.

Now imagine a cow. It’s swimming through the water, hooves thrashing wildly, head struggling to stay above the water, eyes wide and panicky. This is an animal happy solely when all four feet are firmly planted on the ground, and yet the cow is one of the closest living relatives to the dolphin, star of many an aquarium and energetic king of the sea. Cetaceans (the group encompassing whales, dolphins and porpoises) are descendents of a four legged meat-eater that roamed the earth 55 million years ago. The resulting species form some of the most majestic creatures in the sea.

We were welcomed into Indonesian waters by a school of approximately 400 pantropical spotted dolphins in a dazzling display of underwater and aerial acrobatics. The spotted dolphin is a social animal, often seen in large schools made up of numerous smaller family ‘pods’. Dolphins use a series of whistles to communicate with each other and individuals each have a specific whistle to identify themselves, similar to the way your names identify each of you. In addition, toothed whales, which include dolphins, have a unique way of ‘visualising’ the world around them; instead of relying solely on sight they use a technique called echolocation. Sounds are produced by air sacs in the head, similar to you snorting out your nose. In a dolphin, however, these sounds are then transmitted to a large ball of fat in their head, a bit like a bowl of congealing bacon grease sitting in their skull. This ‘melon’ as it is known focuses the sound and results in a string of clicks that spread out through the water, bounce off objects, fish, and other dolphins, and then return to the dolphin giving them an indication of distance, composition and size of the reflecting object. There is however a blind spot, the melon focuses sound above the jaw; any objects below the jaw are not detected. Just imaging not being able to see your feet!

Dolphins have lost the hind limbs of their land based ancestors, and rely on their tail fluke and forward limbs for movement. They can swim at speeds of up to 18mph, slower than the speed you can drive through your local town but about twice the speed of our fastest marathon runner. Spotted dolphins are particularly active and the school we encountered did not disappoint, they put on a display of incredible speed and agility as they danced in the bow wave, leapt clear of the water and circled the boat coming closer and closer, to be met with cheers of delight by the excited crew.

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