ecology of the foreshore, foreshore ecology, gulf of mexico ecology, gulf of mexico shoreline, linda lee rathbun

The Ecology of the Foreshore: Bathing Beauties
Natural Wanders…
exploring the natural world through writing

The Ecology of the Foreshore: The Gulf of Mexico
Story by Linda Lee Rathbun, Photos by Steven David Miller
Introducing Naples Annual Magazine

BATHING BEAUTIES
text by Linda Lee Rathbun

The shores of Naples, Florida are bathed by the mutable waters of the Gulf of Mexico, slipping along her beaches like a gentle, wind-blown caress. Though no other land appears on the distant horizon, it is out there. Just over 100 miles to the west is Mexico's Yucatan Peninsula, the other portal to the Gulf that opens up into a sea one thousand miles wide. Water driven up from the Caribbean by the South Equatorial Current rushes in between Mexico and the western tip of Cuba, and after circulating in swirling ribbons of surface currents, is pushed out through the Straits of Florida to become the southern end of the Atlantic Gulf Stream.
Another great body of water feeds the Gulf at the opposite end of its open passage, the Mississippi River. Her daily contribution of billions of gallons of fresh water turn this land-hugged sea into a fascinating aquarium whose salt content varies by up to 50 percent depending on the season; in winter the water is more saline than in the summer. All the seasons on Florida's southwest shores are magical though - and the sandy stretches
of beach that separate land from water contain a treasure trove of bathing beauties.
We speak of the sands of time and nothing represents the timelessness of nature better than sand. These ivory beaches are made up of incalculable grains, each the broken remains of marine life: coral, calcareous algae, shells and so on. The wind-blown waves are forever pulling at the sand, seeking to shift it and return it to watery depths. In Naples, beach restoration ensures that the elements will not deplete us of our most treasured jewel….not to mention a critical habitat for animals like the nesting sea turtle.
At that ever changing line where the tide-driven water washes up the sandy shore are hidden colonies of tiny beauties: coquinas, miniature shells painted in pastel shades, the twin halves like glossy butterfly wings. Coquinas are one of the few shells that live on beaches, most others are found offshore. As a wave recedes, plant your foot in the wet sand and wiggle your toes. A cluster of exposed coquinas will scramble to rebury themselves in the sand. They are constantly on the move, following the shifting tide up and down the beach, always seeking that narrow, wet zone of lapping waves.
Shells gently rolled up on the Gulf beaches can cast a spell over the most tense of visitors, a slow walk along the shore picking up samples of these beauties is relaxing to the point of intoxication. Our seabed slopes gently to shore, and shells are tumbled up, leaving many of them intact. By taking only dead shells and leaving live shells alone to create new generations of creatures, we have the pleasure of shelling without straining a dwindling species - not to mention confronting a rather nasty smell when the shell inhabitant dies, still clinging stubbornly to its home.
Shells are marine mollusks with a mineral-excreting mantle that envelopes their soft organs; these minerals create the hard shell exterior. Univalve shells are snails living in a spiraled home. They slide along on a single foot and have an operculum, a door that allows them to crawl up inside their shell and shut themselves in. Most univalves spiral to the right; a few exceptions, such as Florida's Lightning Whelk, spiral to the left.
Bivalves are oysters, mussels and clams living in between two mirrored haves, hinged at one end with a powerful ligament. Bivalves are filter feeders, taking in water through one siphon and filtering out the oxygen and food, then expelling the rest of the water through a second siphon. More often than not only half a bivalve is found washed ashore, the other half probably still anchored to a rock on the sea floor. Mollusks have various means of attaching themselves to hard surfaces: sometimes with a tangle of thin threads called byssal, sometimes with the foot, and sometimes with a glue more adhesive than "Super Glue".
Low tide on a full or new moon is a perfect time for shelling. Always check inside the shell though - sometimes a hermit crab will have moved in. If you hold the shell still for a moment, he will poke his head out to see what is going on. Hermit crabs are delightful and sometimes they hold a convention, hoards of them gathering together to swap houses, and all this is done without a real estate agent in sight! A shell book will help identify the multitude of beauties: Slipper Shell, Pen Shell, Jewel Box, Tulip Shell, Jingle Shell, Cockle, Worm Shell, Fighting Conch and many others that make for the prettiest of souvenirs.
Other marine debris gets washed ashore too. Sponges are actually the skeletons of dead animals, living sponge beds are found in deeper water. Seaweed is also washed ashore in great abundance, though what we call seaweed is actually various species of algae, a marine plant that lacks roots, stems and leaves. Seaweed plays an essential role in beaches, for as it is pushed farther and farther up with the highest tides, it begins to form dunes. Sea Oats and Sea Grapes, two critical plants protected by state law, take hold in this sand trapped by the algae, and their deep root system soon snares more sand, stabilizing it.
The Sea Oat is a pioneer plant holding down the foredunes. The Sea Grape grows just beyond it, its fruit a source of food for animals, and the essential ingredient in a favored jelly of early Florida settlers.
Farther inland, especially lining the estuaries that feed into the Gulf waters, are thickets of mangrove trees: the red, the black and the white mangrove. The red mangrove holds onto to its seeds until they are fully formed seedlings, and then drops them in great numbers into the water. They are sometimes called sea pencils. As they float along, the pointy ends become water-logged and sink, while the fruit-bearing ends remain buoyant; and so they bobble along for up to a year. When they find a suitable bedding, they take root, trapping sediment and creating their own land to expand in until a colony of mangroves is formed. Many a Gulf swimmer will encounter these remarkable little floating seedlings, and a boat ride into the mangrove waterways exposes a labyrinth of trees, an essential habitat for marine and bird life.
Other seeds washed ashore are called sea beans. Some, swept up from the Caribbean and South American, are polished and smooth….a delight to run between your fingers. Each sea bean has an air chamber that keeps it afloat, and a hard exterior to protect it. Coconuts are in fact sea beans; they, too, are carried to distant shores by the sea. If you have every walked under a coconut palm and worried about having one tumble from the sky and clobber you on the head, take comfort in this fact: Most palms drop their coconuts between 2 and 5 a.m., a time when most of us are tucked safely away in bed.
An early morning beachcomber wandering the sands in summer is very likely to encounter a set of marks that looks like a tractor tire. These are really the tracks of the endangered Loggerhead Turtle that has come ashore to lay her eggs, usually at night.
The female Loggerhead takes about three hours to pull her 300 pound body up the beach, dig a hole, lay a clutch of about 90 eggs, and then return to the sea. About 60 days later the hatchlings emerge, their sex determined by the temperature of the sand. Following the light of the moon and stars reflected upon the water, they scramble to sea like a platoon of wind-up toys. If by chance you find a lost hatchling confused by artificial lights, take him to the water's edge.
A female loggerhead will lay several clusters of eggs every two or three years. The rest of the time she will migrate throughout the Caribbean, the Gulf of Mexico and up the East Coast as far as Maine.
Looking out to sea, or in the passes that slash through several of the beaches, you can sometimes spot an Atlantic Bottle-nosed Dolphin. Dolphins stick fairly close to shore, following their favorite food of striped mullet. Their streamlined bodies glistening in the sun as they surface to breathe, their ever smiling faces, their close family ties, and their mysterious intelligence make them a favorite. Dolphins are constantly sending out sound waves and analyzing the returning echo to determine the nature of the world around them. They can distinguish between hundreds of outgoing and incoming sound waves each second. Most enviable of all, they seem to have scorned the working life for one of play - a goal most of us spend our entire lives trying to achieve.
Another marine mammal that delights everyone is the Florida Manatee. This gentle and lovable creature is so tame and curious it will swim right up to humans for a closer look. Resist the urge to pet the winsome creatures, however - it is illegal to handle manatees. In winter when the Gulf water is colder, they tend to congregate in inshore spring waters, seeking warmth. Their numbers are small, only about 1,800 manatees remain, making them one of our most endangered, vulnerable species. Cold weather snaps, a loss of habitat such as sea grass meadows, and deadly encounters with speeding boats all pose a threat.
Though manatees may live up to 60 years, they reproduce at a slow rate. A female is about seven years old before she has her first calf, and she will only have one every two to five years. The manatee is a true bathing beauty, its sweet nature and vulnerability making it all the more special - even if it doesn't really look like the mermaid some early sailors mistook it for.
If you enjoy viewing the underwater world with a mask and snorkel, watch for these creatures close to shore. Flat Sand Dollars are found scurrying along the sandy bottom on a furry base of bristles. Sand dollars are actually a type of sea urchin or echinoderm. Anyone thoughtless enough to collect live sand dollars will find himself with a decaying, smelly mess - so if you pick one up and see its bristles still moving, throw it back into the water.
The Nine-pointed Sea Star is often found as well. Also an echinoderm, the Sea Star (commonly called starfish) can regenerate its arms if it loses one - and will grow into two sea stars if cut in half. By human standards, Sea Star table manners are appalling. The creatures disgorge their stomach through their mouth to digest their prey.
Bird lovers will be fascinated by the feathered beauties on Naples beaches. Up above, the black, angular silhouettes of Frigatebirds stand out against the blue sky of summer. Laughing Gulls fuss and squabble with each other in lives that seem to be filled with conflict; near them is often found the Royal Tern, a more delicate and dignified bird with a surprising punk hairdo. Willets wade into the rushing waves, digging up coquinas with their slender bills. Sandpipers, seemingly torn between hunger for critters living in wet sand and a horror of getting their feet wet, are pulled and pushed by the waves in a never-ending clash of needs. The Ruddy Turnstone marches purposefully down the beach, peeping as it tosses aside small stones and seaweed in its search for food. Sanderlings, migrants from their breeding grounds in the Arctic goose-step their way across the sand a short black legs.
The Snowy Egret is the reigning beauty of all beach bathers, especially in late winter. Breeding plumage turns this bird into a breathtaking vision dressed in a lacy veil of feathers accented with long, black legs and bright yellow footwear. Least Terns are the angels of the sky with their distinctive wing silhouette, and a Skimmer working the surface of the water at dusk in a thrilling sight.
Soaring above the beaches are formations of Brown Pelicans, master aviators of the skies. Though they seem abundant on our Gulf waters, they are in fact endangered due to loss of nesting habitat and water pollution in other parts of the country. The mottled brown and gay birds are juveniles, those with white heads and brown sable stripes down their necks are in breeding plumage, and white necks and yellow heads signify courtship plumage.
The pelican is the clown of our beaches. Watch one all tucked up on a piling, or plunging into the sea for a fish, or perched precariously at the end of a slender tree breach, or begging off the pier for fish. This last habit is dangerous. Pelicans suffer greatly from encounters with fishing hooks and lines. Resist the temptation to toss them scraps - bones can snag and tear their pouches, leading to starvation. If you accidentally hook a pelican, do not cut the line. Ask for help, and reel the bird in slowly while the second person captures it in a net. Keeping its wings folded around its body, hold he pelican while the second person carefully removes the line and the hook.
All the bathing beauties of Naples give our beaches their unique character. As the Gulf breeze whispers through the silky strands of sea oats, as waves tumble shells toward the shore, as the warm sand draws us into sleep, the subtropical sun will melt away the worries of the world, reminding us that life is really all about - enjoying and preserving nature's many gifts.

THE END