ELIF #1: The Secret Life of Sand

The beach along Pine Knoll Shores, North Carolina. Personal photo.

Life on an island always seems so idyllic. Miles upon miles of sandy beaches stretching far and wide along the shore and deep into the blue-green waters of the waves beyond. It's a wonderful place to walk, jog, build sandcastles, and lounge in the summer sun. But while people enjoy the beach, many don't consider what the sand might contain and what life it might hide from view.

As an environmental educator, I have had the fortune of experiencing different parts of the eastern seaboard and for the past 7 1/2 months, I have been living on Bogue Banks in eastern North Carolina. One of the topics I get to teach about is about what pieces can be found in the sand that makes up the barrier island. While most people rightly assume that sand is largely made up of eroded pieces of stone and rock that has flowed down from the hills far away, there are so many other pieces that are biotic in origin. 

So many bits and pieces. Personal photo.

The majority of sand on Bogue Banks is biogenic meaning it is largely made up of the eroded exoskeletons, shells, bones, teeth, and scales of the ocean's aquatic life. As a result, the beach is a speckled mix of colors; tan and orange shells, yellow and white crystals, flecks of black and green and dull red stones. Whenever I have walked down the beach, I can't help but compare the different layers of sand that are present on different parts of this dynamic habitat.

All beaches are broken up into three tidal zones that relate the water in different ways. The supratidal zone is where the dunes crest over the lower beach. They are often covered with plant life which is instrumental in the sand maintaining its structure and towering form. The roots of the American beach grass (Ammophila breviligulata) and sea oats (Uniola paniculata) act as scaffolding for the sand to remain in place, allowing it to protect the inland portion of the island. That being said, it hasn't stopped water from overwashing in the past and parts of the dunes have been compromised by ambitious hotel and home builders looking to capitalize on American's love of waterfront property. 

Further down the beach, you have the intertidal zone. This is the part of the beach that holiday makers and vacationers love. This is usually the flat, open section that makes for a nice place to prop one's picnic cooler, umbrella, windbreaker, towel, cooled beverage containers, and swimming costumed self while enjoying the warm rays of the sun. It is also the place where the most action is experienced by the animals that live there. Migratory shorebirds like willets (Tringa semipalmata) and sanderlings (Calidris alba) are frequent visitors to this zone and use some clever methods to capture prey from the waves.

Sanderlings are best known as the clockwork birds which run towards retreating waves to gather coquinas and sand fleas before retreating themselves from the next advancing waves. Willets, being taller and longer billed, don't mind getting their feet wet and will often wade up to their bellies in order to root deeply for similar prey. Throughout the day, these birds forage along the waters edge as it rises and falls with the tidal cycle. 

Spring sanderlings. Personal photo.

Wading willet. Personal photo.

In the water itself lurks the subtidal zone and the powerful current that dictates the journey of sand throughout the year. This longshore current carries sand along the ocean side of the island and deposits large amounts on the eastern side in the inlet between Bogue Banks and Shackleford Banks. As the tides rise, water rushes into Bogue Sound bordering the back of the island and the mainland and carries even more around the back. The movement of sand has many consequences. Most noticeably for human beings, it means that land available for building on gets scarce or wears away what is already there. For animals we like to eat like clams and oysters, it means your home is always shifting, always moving, and requires you to trust that your surroundings won't betray your presence. 

For clams in the ocean, they have the fortune of a tumbling ocean to cover them like a rich quilt for a few hours a day. In the sound, it's more like a sheet that reveals more than the occupants would like. This means being under constant threat from a ubiquitous resident of the shore: the seagull.

A laughing gull (Leucophaeus atricilla) sounds off. Personal photo.

The word seagull is one of those words that really upsets hardcore birders. I don't get as bent out of shape if I hear someone say it these days, but it doesn't stop me from wanting to correct them. Just this week, I saw a viral post from the BBC about a man being allowed back into a Canadian hotel after 21 years because he'd accidentally left an open package of pepperoni on the open window of his room and when he had returned, a flock of 40 Western gulls (Larus occidentalis) had helped themselves to the freebie. Even in the article, the caption under the photo of two gulls read "Western seagulls". Gulls are ever present on Bogue Banks. Not only is it their natural habitat, some of their favorite foods can be found in the waters around the island. On any given day this spring, the dock leading out to the sound has been littered with the shattered exoskeletons of clams called quahogs (Mercenaria mercenaria).

Quahogs, also known as hardshell clams, are well known along the Eastern Seaboard. Anyone who has dined on classic New England clam chowder (the best kind in my humble opinion) has likely consumed the flesh of these common bivalves. In one of his celebrated books, Stalking the Blue-eyed Scallop, Euell Gibbons described the quahog as "... a roundish clam, and the full-grown ones may be 4 to 5 inches long and a little less across. In the South they grow even larger. The color is grayish white outside and creamy white inside, usually with one edge deep purple and sometimes with other purple splotches."

Shattered like glass. Personal photo.

These purple marks give the quahog the well deserved nickname of the "wampum clam". Wampum was a combination of white and purple beads that were created from the broken pieces of quahog and whelk shells and was used by tribes along the East Coast of the United States as a trading item and status symbol. The pieces were drilled using stone tools and whittled down to beads no larger than 1/4 inch long. These beads were then strung together using plant cordage or animal sinew to create a beaded belt or sash that would indicate rank within a tribe.

When the colonists arrived in the 1600s, the recognition of wampum as currency was established and was used by the natives and colonists alike. While researching more about wampum, I stumbled upon an intriguing article I found at Indian Country Media Network which describes how, in 1650, the Massachusetts Bay Colony determined that "...strings of 8, 24, 96, and 480 beads were valued respectively at one, three, and twelve pence and five shillings." Nowadays, modern wampum beads can be bought online and are quite pricey if finished well. I found beads that were selling online for five to twelve dollars a piece! Even if they don't have the same meaning today, they are clearly still valuable. 

Graveyard of the Bivalves. Personal photo.

That's why I've been collecting the scraps left by the gulls. The larger species like ring-billed (L. delawarensis) and herring gulls (L. argentatus) use their human resources to their advantage. What do I mean by that? Well, if you've ever parked in a tarmac lot next to a beach in the summer, you have no doubt noticed the dozens of broken shells in one corner of the lot. For the gulls, any hard object becomes their anvil. On Bogue Banks, one of those anvils are the docks reaching into Bogue Sound. As the spring equinox came and went, the frequency of the broken shells showing up on the dock grew exponentially. Some days, it feels like you're literally walking on egg shells. 

In a few instances, I have come across shells that haven't cracked and instead have been left by the gulls to rest on the anvil. I can only imagine what the clam might be thinking. Though they lack a brain per se, they do react to changes in water height, salinity, and flow. They are filter feeders, taking in water through one siphon (incurrent) and pushing the waste and filtered water out of another (excurrent).

Recently, I have been inspired to make my own jewelry from the shells I find on the beach. This 

isn't unusual given them abundance of different shells that either wash up or are revealed as the sand shifts daily. Huge chunks of surf clam (Spisula solidissima) shells, deeply ridged scallop and cockle shells that make for excellent succulent plant pots, and the small, multicolored coquinas that live in the surf tossed sand plied by willet and sanderling alike. My favorites to find and pick up are the worn Eastern oysters (Crassostrea virginica) that have been dragged along the edge of the island via the current for decades at a time. While living, the shell of an oyster is notoriously sharp and can give people some nasty cuts if they wander into an area without adequate footwear. After the animal dies, the shell might spend the next few decades or even centuries drifting along in the current, getting buried and uncovered and buried once more. The shell gets worn smooth and starts to resemble a wrinkled fold of black plastic rather than the flaky mica-like shell they wore in life. What attracts me to these shells in particular is their appearance with years of grinding, shaping, wear and tear. I can only wonder what they experienced both in life and in their afterlife.

This weekend, after smashing quahog after quahog with a hammer, I thought about the clam's status today. It's still valued as jewelry and although I initially thought that can be appreciated for its beauty without destroying it, I reminded myself that without the initial termination of its life, one wouldn't even be able to enjoy the rich purple edging of its shell. Without the destructive smashing by the gulls, I wouldn't have shells. Without the hammer, I couldn't get the purple bits. Without the erosion of the shells, we wouldn't have sand and by extension, an island to stand on at all. The connections were all there and I thought about how it might feel to be a clam that escaped being smashed. In fact, I remembered just such a clam from a few weeks earlier. I was on a walk along a forested trail on the property I live on and before me a quahog was resting on the path in front of me. I stared at the clam for a moment, puzzled and stunned. Where had it come from?

The quizzical clam. Personal photo.

The most likely scenario is that a gull had dropped the clam from above and expected it to open upon impact. When it didn't it either couldn't approach because the foliage above was too thick or it really wasn't that hungry. I snapped a few photos and picked up the clam. The trail led down to the shore of the sound, so I decided to return it home. I thought about how returning it might give it a chance. It reminds me of the story about the boy throwing starfish back into the sea after a storm. 

The story, written and adapted from The Star Thrower by Loren Eiseley,  goes like this: 

"One day a man was walking along the beach when he noticed a boy picking up and gently throwing things into the ocean. 

Approaching the boy, he asked, "Young man, what are you doing?" 

The boy replied, "Throwing starfish back into the ocean. The surf is up and the tide is going out. If I don't throw them back, they'll die." 

The man laughed to himself and said, "Do you realize there are miles of miles of beach and hundreds of starfish?" "You can't make any difference." 

After listening politely, the boy bent down, picked up another starfish and threw it into the surf, then smiling at the man, he said; "I made a difference to that one."

And for that clam, so did I. 

"All art is autobiographical; the pearl is the oyster's autobiography." - Federico Fellini