Posts Tagged 'shells'



Basic beach

I live on an island. It’s a rather lengthy island, and so, unimaginatively, it’s been called “Long Island” for several centuries now. I’m on its far western end, in the once-upon-a-time city and now borough of Brooklyn, which, uh, doesn’t really think of itself as being a part of “Lon Guyland.” The reasons for this are complicated — historical, political, social, satirical — but not very geographical. For, if you head eastward from here, following either of the two terminal moraines created during the last ice age, you eventually hit the water. But the moraines continue, emerging in Block Island, the Elizabeth Islands, Cape Cod, Martha’s Vineyard, and finally, Nantucket (where, once upon a time, I graduated from high school). It was originally all one stretch of land, now divided up by the invading ocean. So there are quite a lot of similarities still.Take these typical bivalves, for instance. This picture was taken on the north shore of Nantucket, but if you comb any beaches around here (Brooklyn), you shouldn’t find these unfamiliar.

Clock-wise from the top: soft-shell clam, Mya arenaria, the “steamer clam” or, for the less polite, the “piss clam”; blood ark, or blood clam, Anadara ovalis, so called because the mollusk has red blood, which is most unusual for a mollusk; common slipper shell, Crepidula fornicata; both halves, or valves, of the quahog, or hard-shell clam, Mercenaria mercenaria; Atlantic oyster, Crassostrea virginica (the ridges on this specimen are unusual); common or blue mussel, Mytellus edulis. I found a nice example of an Atlantic jackknife clam (which we always called “razor clams,” but there’s another species that shares this common name),Ensis directus, a few minutes after I’d passed the composition above: Note the tan coloring here, also seen in the soft-shell clam in the first image: when alive, these shellfish have a skin-like covering to their shells, called the periostracum. In the case of blood arks, it can be hairy looking. The material wears off as it meets the merciless exposure of the beach.

Winkles

Four shells collected at Cape Anne, Massachusetts. The three clustered around the illustration are Common European Periwinkles, Littorina littorea. This winkle, much savored by Old World palates, was first recorded in the Gulf of St. Lawrence in 1840, perhaps arriving via rock ballast in ships. Another source says they may have arrived much earlier, upon drifting logs before the Europeans themselves arived on more ornate drifting logs. However they got here, they’re now established on both U.S. coasts and they tend to be bad news for the ecosystem. We should probably be eating them, too.

The white shell on the left is an Atlantic dogwinkle, Nucella lapillus, one of the native species beset by competition and habitat transformation resulting from the abundance of European periwinkles.

Ribbed Mussels

The Atlantic ribbed mussel, Geukensia demissa, at low tide at Calvert Vaux Park. Unlike the more famous (because delicious) blue mussel, Mytilus edulis, the ribbed mussel, which is found up and down the East Coast, prefers brackish waters. They are a keystone species for salt marsh habitat and vital to Jamaica Bay. Establishing beds within the roots of cordgrass like Spartina, the clumps of mussels help to stabilize the plants while providing nutrients for them. They are also food for gulls and I assume other shore birds like oystercatchers. One source notes that while they are edible for humans, they have an unpleasant taste — which I would have thought was a good definition of inedible.
Any port in a storm.

Down the Shore

During last month’s spring tide, we went down to the end of Flatbush Avenue to wander along Brooklyn’s shoreline at Dead Horse Bay. Spring tides, which occur just after full moons, result in unusually high high tides and unusually low low tides. The water level was the lowest I’ve ever seen it out there. (Note that the spring here is not the season, for spring tides occur throughout the year, but rather the verb; the tide springs ashore.)
Moon jellyfish, Aurelia aurita. They have a mild sting in the water, but are supposedly safe when dead on the beach — although I’ve never tried to confirm that. This is a common species in our area, and are found on both bay and ocean beaches. (Recently, on another beach, in much colder weather, we found a bunch of them frozen — this is probably a delicacy somewhere, calling Iron Chefs!).
Some kind of acorn barnacle. These crustaceans begin their lives as free swimming creatures, then glue themselves headfirst to a surface, often in the intertidal zone, for the adult stage of their life. Modified feet reach out to draw in plankton to eat. Darwin was mad for them. When the tide pulls out, they close up the six plates of their shell and wait for the return of the water. Dead Horse Bay, with its litter of old exposed along the shoreline, has some interesting surfaces for them to anchor on.
This is a false angel wing clam, Petricolaria pholadiformis. This species is found up and down the East Coast, but the shells are rather fragile and rarely survive the tumble of the wash-ashore. In fact, this was the first time I’ve ever seen one whole. It was far from the water, and probably dead, but we put it back into the water, anyway, just in case. Later we found some of the empty shells; they might be thought of as fallen angel wings, at least by the Miltonians amongst us.

Yes, it’s cold. Yes, the wind can be fierce. But there are few things more invigorating than walking along a beach this time of year.

Clam clamor

Much of my project here is about looking at things in the natural world. Looking, and discovering, and sharing. This is just a fragment of clam shell that I picked up at JBWR last weekend, but I was delighted by the detail. Click on the image to open it up: you can see the animal’s successive stages of growth.

Clams add a new layer to their shells each year, so these are like the growth rings in trees. The earliest little nub of a shell, smaller than my pinky nail, is still here. This vestige is the umbo, or beak.

Such hardshell clams can live a quarter century, but they have the unfortunate characteristic, for them, of being delicious throughout their lives.

Hardshells are also known as quahogs, which is a wonderful word taken from the Narragansett “poquauhock.” The scientific name Mercenaria mercenaria points to the famous wampum, the internal purple edges of these bivalve shells, which were carved into beads by the original Americans. (Europeans introduced the idea that wampum was money.) The pink hearts of whelks were also used. Long Island, whose southwestern end shelters Brooklyn, was known to the originals as “the land of the shells.” Older sources called this species Venus mercenaria, the goddess of love on the half shell.

In the clam eating business, the hardshell clam is also called the little neck and the cherrystone, raw bar stalwarts, depending on age. “Quahogs” are older, hence tougher, and used in chowders, and in that Manhattan clam and tomato soup that is tasty, but not, I’m afraid, chowder.

A fragment, to be sure, but one rich in biological, historical, linguistic, and culinary associations.

BTW, the specimen was posed on the surface of a surf clam picked up at Fort Tilden. But that’s another posting…


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