No. 19–The Beach

When you stroll the beach at Hunting Island State Park you are walking on the detrital remains of mountains. The sands of the coastal plain are the erosional deposit of ancient river systems that once carried, bit by bit, upstate mountains to the sea over the eons. That mountain to sea transport system is no longer in place due to the damming of rivers which is a contributing factor to present day beach erosion. Our beaches are no longer replenished by natural forces.

While granite quartz from the Appalachians is by volume the greatest constituent of local beach sand, the pulverized shells of marine mollusks and organic detritus are also in the mix. As mentioned in a previous column, a fair amount of estuarine produced detritus is delivered by outgoing tides as food for both beach and near shore creatures.

Speaking of creatures, there are two species of hermit crab found on local beaches during the warm months. The long wristed hermits are the little guys found scurrying about in tidal pools and surf edge. With close observation you will see they have long thin claw arms which gives them their common name. Upon peering into a shell you may observe two light tan claws filling the opening. That is the flat claw hermit which grows considerably larger than its neighboring cousin.

Keep in mind that a small hermit crab is able handle a shell large enough to completely disappear in when disturbed. Also keep in mind that it’s illegal to remove any living creature, except for fish you’ve caught, from the beach. A flat bottom container will enable you to make sure the shells you take home won’t wander off when you’re not looking. Simply place collected shells open side up in the container and do not disturb for fifteen minutes or so. When next you look, any shells that have turned top side up have someone living in them and should be returned. Also, please don’t get carried away with your shelling as every snail shell removed from the beach represents the loss of one housing unit in a not unlimited marketplace.

Sand dollars have long been a favorite beach keepsake. And yes, Virginia, those you find either are or once were living creatures. The upper side of a living sand dollar is fuzzy and a purplish brown in color. On the underside you will observe the little tube feet waving like wheat in the wind. Key hole urchin is the name given this species as sand dollars are in the urchin family. A related species, the sea biscuit, inhabits off shore waters and rarely if ever found on the beach.

The primarily nocturnal ghost crabs form the late shift clean up crew scavenging organic remains left by the tide. The down side of them is they also prey on sea turtle eggs. The speedy creatures live in holes dug high on the beach. They may, on occasion, be observed during the day making a mad dash down to the surf and back again. They must do this periodically to wet their gills to enable them to take oxygen directly from the atmosphere.

One item found on the beach that regularly stumps folks is a slightly translucent, hard rubber like amorphous blob ranging from white to gray to pink to orange in color. It is a colony of filter feeding tunicates sharing a sheathing epidermal layer with the common name of sea pork.

Sea whip coral (a soft coral) often washes ashore after being ripped loose from holdfasts by working shrimp boats. The most common colors of the pliant branching colonies are yellow and purple while red, orange and even white are not unknown. Sea whip would be the lone exception to the rule of taking nothing living from the beach. Once dislodged it is doomed to desiccation on the shore. If found still wet it may be placed in a container of sea water and the delicate polyps observed as they open to feed on plankton. It may be taken home for use in dry arrangements but keep in mind that it will be odiferous for a time as all dead creatures are.

An ocean beach is never the same from day to day. The change may range from subtle to dramatic as determined by climatic conditions. There are also broad seasonal changes dictating the abundance or paucity of life that may be observed. AS part of my job I collect beach specimens for the Estuarium from time to time. Often I head for Hunting Island with a specific species or two in mind and invariably they’re not to be found. Each time, however, I am rewarded by finding something totally unexpected or by observing something for the first time which adds to my base of knowledge. The nature of the surprises that nature provides makes each outing uniquely gratifying.