Sea stars (sometimes called “starfish,” even though they’re not actually fish) rarely do well in home aquariums. Many species starve to death, either quickly or over extended periods, which is unfortunate because sea stars are fascinating creatures to watch, and often brilliantly colored, too.
I’ve tried to stay away from acquiring sea stars, because I don’t like bringing home creatures that won’t thrive in my aquarium. For a while, I had a thriving population of micro-brittle-stars (which measure 1-2 inches in diameter, from arm to arm). Sadly, I lost them due to an unexpected (and largely unpreventable) salinity shift a couple of years ago. I’m on the hunt for more, because they’re easy to keep on a reef like mine.
About a year ago, I decided to take a chance on a Linckia star–a peaceful family of sea stars that feeds on bacteria and reef detritus. (The Family is named for J.H. Linck, who wrote a book about sea stars in 1733.)
I brought my new star home attached to the rock it was sitting on, because their tiny feet are fragile, and can be injured if you try to remove them by force. To my surprise, when I removed the rock from the acclimatization bath, I discovered a second Linckia star–a blue one, which was in the process of re-growing a body and four new limbs from a single leg.
Sea stars have the ability to re-grow new legs when one gets lost or damaged, and can actually reproduce by shedding entire legs, along with sections of body tissue. If the leg has enough body cells attached, it can regrow its body, and new legs, thereby becoming an entirely new starfish.
For reasons which will be obvious to pop-culture fans of a certain age, I named the little blue starfish “Thing.” (At which point, the tan one became “Cousin It.”)
Many months later, Thing and Cousin It are both doing well. Thing has continued to grow, and though it still looks more like the tail wagging the proverbial dog (or, more properly, wagging the star), the fact that it’s healthy and growing is nice to see.
Cousin It is thriving, too, and makes regular appearances along the back and sides of the tank, as well as journeys across the front.
Most commonly, I see Cousin It on the reef, wrapped around a coral or squeezed into a crevice between the rocks, where it feeds on bacteria and detritus that thrive in narrow spaces.
Sea stars are interesting pets, because on a reef like mine you don’t actually see them all that often. Often, a week or two passes without a sighting, and then I’ll see them around for several days as they graze across the visible parts of the tank. Their off-and-on presence serves as a nice reminder that even though much of nature isn’t visible to us all the time, millions of creatures are out there, going about their peaceful business just out of sight.
And every once in a while, if we keep our eyes open, we’re lucky enough to catch a glimpse of a world that isn’t really dull at all.
It’s full of stars.
Have you ever seen sea stars up close? Did you know they’re not really fish at all?