Beach Walks with Dr. Joe Lettered Olive Snails By Dr. Joe Richardson Possibly the most attractive shells that you’ll find beachcombing on Tybee are those produced by Lettered Olive Snails. The torpedo-shaped Lettered Olive shells have a polished, glossy surface that makes them particularly desirable beachcombing treasures. Examine the shiny brown shell closer and you’ll notice the tiny triangular arrangements of darker and lighter lines that appear to make “letters” like M’s, V’s, and W’s. No two Lettered Olive shells have the same patterns, so each shell is unique. Although you can find Lettered Olive shells year-round on Tybee, I’m choosing to discuss them now during the late spring because this is when we are most likely to come across live ones on our beach (or maybe I 26 TYBEE BEACHCOMBER | MAY 2017 should say “in” our beach). Some days you might not see any; but there will be other days when they are there by the dozens. You will find them in the wet intertidal zone sand, usually from about mid-tide level down to the water line at low tide. Some of them might be lying on top of the sand, but most of them will be burrowing just below the surface, so you might walk right over them unless you know what to look for. Lettered Olive Snails are predators, and they are hunting for small animals living just below the surface of the sand. With their torpedoshaped streamlined shell, Lettered Olives dig and plow through the sand using their muscular foot. They also produce lots of slime that helps when digging through the sand. When a Lettered Olive snail encounters its prey, it surrounds it with its foot and essentially suffocates it and then eats it. Perhaps you have seen pretty, empty Coquina clam shells that look like tiny colored angel wings. Most likely, it was a Lettered Olive Snail that captured and ate the animal from inside those colorful shells. Sometimes the trails of burrowing Lettered Olive Snails are easy to spot. They look like somebody dragged their finger or a stick across the wet sand creating a shallow narrow trench. If you see a hump of sand at one end, that is probably the digging snail. Other times the snail might have just started digging so there isn’t much of a trench but more of just a small disturbance where the sand is slightly lifted up. If you see that, check under that bump and you might find the glossy-shelled snail. You can tell if you’ve found a live Lettered Olive Snail by looking inside the shell opening. If it’s alive, you’ll be able to see a portion of the beigecolored muscular foot just inside. You don’t want to keep a live one. It’s just going to die and stink. Besides, Tybee protects its shore life and doesn’t allow removal of live animals from the beach. Instead, dig a little trough with your finger, put it in there, and cover it up. Or carry it down to the really wet sand, set it there, and it will probably start digging. Dr. Joe Richardson is a retired marine science professor with 35+ years of research and teaching experience along GA and the southeastern coast and Bahamas. Besides research, he conducts Tybee Beach Ecology Trips year round (www.TybeeBeachEcology.com) and frequently posts pictures of what they are finding on his Tybee Beach Ecology Trips Facebook page.
20031TB
To see the actual publication please follow the link above