This afternoon, after I got off work, I put on three extra layers of clothing and my wool hat and braved the cold, wind, and rain to walk on the beach.
Yes, I swear my camera was not set to black and white when I took that photo – it really was a grayscale landscape. The advantage to going on such a dreary day was that I had the beach all to myself, at a time when the unsettled weather meant that the waves had been dredging all sorts of pretty things up onto the shore.
At the south end of the island, I was surprised and delighted to spot several Laughing Gulls whose black hoods had almost completely grown back in – a sure sign of spring? – plus there were about half a dozen skimmers around, which I hadn’t seen for a while.
By far the best find, however, was a knobbed whelk shell as long as my hand, the biggest once I’ve ever come across. When I spotted it it was mostly buried in the sand, and I couldn’t believe my luck when I pulled it out and discovered that it was intact, empty and whole and perfect.
I’m not a big shell collector most of the time. What would I do with boxes full of shells? Better to leave them for the hermit crabs, who can put them to good use. But this one, heavy though it was, absolutely had to come home with me. When I flipped it over…
…its rough gray outside revealed an impossibly brilliant red-orange interior, one warm spot of color on the grayscale beach.
I am and always will be a forest person at heart, but that doesn’t mean I won’t miss walking on the beach every day when I leave Georgia. Ambling along the wrack line, seeing what the waves have turned up today – it’s never the same twice. The tide will carve a deep runnel midway up the beach…
…only to smooth it out again the next day.
…live keyhole urchins, and their remains, which we call sand dollars…
…fist-sized knobs of “sea pork,” a colonial tunicate, which probably resembles our distant ancestors: its tadpole-like larvae have notochords, primitive “backbones” which make this one of the oldest chordate animals.
Eventually my walk takes me to the southern tip of the island, where a mixed flock of sanderlings, dunlins, willets and oystercatchers has congregated at the remains of a shrimp boat that wrecked here decades ago.
I sit on a piece of driftwood for a while, contemplating the view, before returning the way I came. Not a bad way to spend a sunny Sunday afternoon.
One must-discuss mollusk (say that ten times fast) during every beach class I teach is the moon snail (family Naticidae). What middle school student – heck, what person – wouldn’t be fascinated by an animal that uses its tongue to drill holes in the shells of other animals and eat them alive? And sometimes practices cannibalism? The life history of this critter, identified by its round, smooth, spiral shell, is guaranteed to earn wide eyes and “Wow!”s from any group of sixth-graders.
The telltale sign that a moon snail has been up to its mischief is a clam shell with a small round beveled hole drilled through its end.
When I was a kid, I found a shell like this and strung it on a length of red yarn to turn it into a necklace. Never did I pause to wonder how the heck the hole got there. When I finally learned about moon snail predation a couple months ago it was like I was a cartoon character with a light bulb going off above my head. Aha!
Moon snails, you see, have a long, minutely toothed, tongue-like appendage called a radula, which (in combination with acid secretions) they use to drill a hole through the shell of their bivalve prey. Then they insert their proboscis into the hole to consume the fleshy animal inside. Alive. Whoa!
Better still, they don’t limit their ravenous rampages to clams. No, big moon snails are quite happy to eat small moon snails. Finding a little moon snail shell with the telltale hole during beach class is a guaranteed crowd-pleaser.
Cannibalism! Acid secretions! Drilling holes with its tongue! It’s like a horror movie monster, washed up right here on our beach. Who knew there was so much drama in the world of seashells?
When I started this job, I bought a little notebook of unlined paper to double as journal and sketchbook. I can’t claim to be much of an artist; the only time in the past I’ve done anything resembling nature sketching was when I took ornithology in college and used drawings to record data on, say, feather maintenance behavior, and those were basically the bird equivalents of stick figures.
Yeah… obviously birds that are on the ground sitting relatively still are easier to draw than birds in flight.
Inanimate objects are much easier.
Before starting this job I would have looked at this and seen nothing but a collection of pretty shells.
I mean, sure, I could have told you they were bivalves, in phylum Mollusca. I do have a degree in zoology. But I couldn’t have said whether these were the same species, or different, or what. In fact, what you see are representatives from three different families of clam: cockles, scallops, and arks.
Here they are seen from underneath, clockwise from the top left, with some helpful highlighting added by yours truly.
The trick to identifying them is to look not at the sizes and colors, which can vary, but at the hinge (the place where they would connect to their missing other halves). Cockles have a curvy indentation, scallops (yes, the same ones you order in seafood restaurants!) have triangular “ears” sticking out on either side, and arks are just straight across. Now the next time you go for a walk on the beach, you can wow your friends with your bivalve-identifying ability!