Sand sea stars are some of my favourite starfish – they move across the sand at an incredible pace, seeming to exert no effort. That’s what having hundreds of tube feet will do for you! Also, I’ve never seen a less than perfect specimen. Perhaps they are risk-averse and don’t do stupid things that cause them to lose limbs.
On a recent dive with a group of Tony’s Open Water students, I discovered another talent they have. Divers will be aware that a group of Open Water students moving across the sand creates an effect akin to the meeting of an underwater landslide and a tsunami. It’s for this reason that I like to swim in front or to the side of such a group… Not only are kicks in the head virtually a certainty, but the cloud of sand makes it impossible to see anything. For some reason on this dive I found myself at the back. (It’s actually not unusual – I get left behind quite often when something photogenic catches my eye.)
The massive current system created by three pairs of frantically bicycling fins had flipped a sand sea star over onto his back. As I watched, he righted himself, in an incredible display of strength. I could imagine him saying “Gnnnnnnnh!” with the effort as he lifted one leg straight up while raising himself on another two of his limbs.
He started a rolling motion after getting one leg fully vertical and having flexed the legs on either side to their maximum potential.
The relative density of his body (which is actually full of water) and the water around him meant that he couldn’t just rely on gravity to finish the job at this point. The descent onto the sand took place in slow motion.
I am sure he just wanted to slap that last leg down triumphantly. Take that!
We both breathed a sigh of relief as he completed the process. My camera doesn’t have a burst mode, so there’s a pause of a couple of seconds between each photo. I think he took about 10 seconds to right himself. I was very impressed.
