South Shetland Islands
Tranquil, gelid and more than just a touch surreal, that’s what it’s like at 150 feet below the surface of the Southern Ocean. This is a shot from our Remotely Operated Vehicle, our camera-toting robot who never gets cold, does not breathe and can not suffer the bends or nitrogen narcosis like a diver. Its halogen light illuminates the feathery branches of a crinoid and the belly of a sea cucumber, center and right side of the picture, respectively. They seem to quiver in the warmth of the beam and move closer to the camera even as they stretch out their feeding appendages. Like two basketball players each seems to try to reach over the other. Or do they? What can they see with no eyes in a world frozen just before the sparse light of dawn? See, maybe not, but they can both sense small changes in their twilight. If they don’t like it they can move. While it’s not light they’re after, but rather tiny water-borne plants and animals, they need their own space to work and each is lucky they did not take up residence next to a large and pugnacious anemone with strong, sticky tentacles studded with vicious stinging cells. But what’s a crinoid anyway and don’t most sea cucumbers just suck mud like elaborate worms? Crinoids are an ancient group related to sea stars. If you collect fossils you should be familiar with the stalked crinoids; this one, however is a modern feather star. With its twenty arms it catches passing food with tiny, sticky tentacles all along the feathery surface. The tentacle then whips the victim into a groove lined with even smaller hair-like structures that rhythmically beat and move the meal down, down to a lip-less, gaping maul. Now the sea cucumber is also related to the sea star and yes, many if not most are mud suckers, but in this environment, rich with tiny plankton, there are often filter-feeding sea cucumbers. These here are relatively large, about ten to twelve inches long and they sit on their ‘butts’ and often with a rock behind them for support, bend their pickle-like bodies upward to reach as high as they can into the rich planktonic soup. They too, like the feather stars, have tentacles or arms to feed with, but they are not stiff. One by one the sea cucumber bends an arm and takes it deep within its mouth to suck off its meal. It is a slow process here; most things are, and it can take several hours to complete a single circuit of the arms. Bend and suck, stretch it out, then bend and suck again, all day and all night. But what else is there to do if you can not even dream about tomorrow?
Tranquil, gelid and more than just a touch surreal, that’s what it’s like at 150 feet below the surface of the Southern Ocean. This is a shot from our Remotely Operated Vehicle, our camera-toting robot who never gets cold, does not breathe and can not suffer the bends or nitrogen narcosis like a diver. Its halogen light illuminates the feathery branches of a crinoid and the belly of a sea cucumber, center and right side of the picture, respectively. They seem to quiver in the warmth of the beam and move closer to the camera even as they stretch out their feeding appendages. Like two basketball players each seems to try to reach over the other. Or do they? What can they see with no eyes in a world frozen just before the sparse light of dawn? See, maybe not, but they can both sense small changes in their twilight. If they don’t like it they can move. While it’s not light they’re after, but rather tiny water-borne plants and animals, they need their own space to work and each is lucky they did not take up residence next to a large and pugnacious anemone with strong, sticky tentacles studded with vicious stinging cells. But what’s a crinoid anyway and don’t most sea cucumbers just suck mud like elaborate worms? Crinoids are an ancient group related to sea stars. If you collect fossils you should be familiar with the stalked crinoids; this one, however is a modern feather star. With its twenty arms it catches passing food with tiny, sticky tentacles all along the feathery surface. The tentacle then whips the victim into a groove lined with even smaller hair-like structures that rhythmically beat and move the meal down, down to a lip-less, gaping maul. Now the sea cucumber is also related to the sea star and yes, many if not most are mud suckers, but in this environment, rich with tiny plankton, there are often filter-feeding sea cucumbers. These here are relatively large, about ten to twelve inches long and they sit on their ‘butts’ and often with a rock behind them for support, bend their pickle-like bodies upward to reach as high as they can into the rich planktonic soup. They too, like the feather stars, have tentacles or arms to feed with, but they are not stiff. One by one the sea cucumber bends an arm and takes it deep within its mouth to suck off its meal. It is a slow process here; most things are, and it can take several hours to complete a single circuit of the arms. Bend and suck, stretch it out, then bend and suck again, all day and all night. But what else is there to do if you can not even dream about tomorrow?
