Why Carolina bays are an enduring mystery
Earth still holds secrets. Among those secrets, what formed the Carolina bays, Earth’s most mysterious landform? People drive by them without a clue as to what they’re seeing. A swamp they think. Were they to fly over them, however, they’d see elliptical, parallel landforms running northwest to southeast. That appearance spurred theories that a meteorite bombardment created the unusual landforms we call Carolina bays. Isolated wetlands, they overlap and occur as smaller bays inside larger ones. They vary from a few square feet to thousands of acres. North Carolina’s Lake Waccamaw, at 5.2 by 3.5 miles (8,938 acres) is one of the larger bays.
“Carolina bays” has nothing to do with coastal waters. “Carolina” refers to the fact that the most and best bays concentrate in the Carolinas. “Bays” refers to the prevalence of bay trees, especially sweet bay, red bay, magnolias, and laurels that grow in them.
From 500,000 to as many as a million bays dimple the Atlantic Coastal Plain from New Jersey to Florida and Alabama. While aerial photos of Carolina bays bring to mind the moon’s craters, bays are far from barren. They’re fragrant places heavy with the scent of flowers, orchids, and the oil of cypresses. To step into an undisturbed bay is akin to going to Africa. They teem with wildlife thanks to their diverse habitats and are hauntingly beautiful. Pond cypress swamps, savannas, and snow-white sand rims host an amazing abundance of wildlife. Venus flytraps, pitcher plants, sundews, snakes, alligators, and deer find sanctuary in Carolina bays.
Bays are feather-rich … herons, egrets and migratory waterfowl flock to them. Raccoons, skunks, otter and opossums find food and water in Carolina bays. Salamanders and frogs, especially, thrive in Carolina bays, which provide important breeding sites. Black bear, deer and alligators live in the bays as well.
Winter and spring rains fill the shallow depressions with water, and thanks to rain, Carolina bays represent the coastal plain’s dominant freshwater wetland feature. One season they’ll have water; another they won’t. Summer and fall dry them out, and plants and animals come and go with seasonal rains. Temporary water is a good thing. The absence of longstanding water prevents predatory fish from getting established, a benefit to amphibians. The threatened frosted flatwoods salamander, for instance, only lays its eggs in dry ponds. That guarantees no fish will eat their larva when rains refill the bay. Thus Carolina bays provide much-needed breeding sites for amphibians.
Where did they come from?
This 3D representation precisely illustrates the bog’s elliptical shape and orientation. LiDAR, or Light Detection and Ranging, is a remote sensing method that uses a pulsed laser to measure variable distances. (Photo courtesy of Michael Davias)
As origins go, Carolina bays elude a definitive, comprehensive answer. What formed them, and when did they form? From meteorite and icy comet bombardments to volcanoes, sinkholes, and nesting whales, no one theory comes out on top, though Ray Kaczorowski’s “Oriented Lake Genesis” theory enjoys more traction than others. In 1977, research led Kaczorowski to believe that Carolina bays evolved from strong prevailing late Pleistocene winds on shallow, ponded water. Over time, the wind oriented the lakes and sandy edges took on elliptical shapes. Kaczorowski’s NASA-funded report sought to debunk the celestial impact theory by finding the puzzle’s missing piece. Where might comparable landforms exist under similar surface influences? Kaczorowski found what he sought in east Texas, Chile, and on Alaska’s North Slope: wind-oriented lakes he suggested were bays “in the making.”
Even if scientists think they know how their shapes formed, they don’t know what created the depressions themselves, but what ancient wonders they are. Various dating techniques place them at 30,000 to 100,000 years old or older. No “new” bays appear to be in development, although certain high ponds could be bays in development. We can’t be sure as we don’t have a definitive origin theory.
Bays’ depth ranges from a few feet to as deep as 40 feet. Many have peat bottoms. It’s an oversimplification but think of them as oval saucers sunk into land above the water table. To replicate Carolina bays, press various-sized spoons lightly into the earth, making all impressions parallel. For greater precision orient your indentations northwest to southeast. Imagine the wider northwest end being filled with pond cypresses standing in blackwater. In the middle of the depression imagine a savanna. At the smaller, southeastern end visualize a rim of white sand. Put a bit of water in several depressions. Stand over the dimpled clay with these images in mind and you get a rough notion of how they look from far above.
You can’t talk about Carolina bays without mentioning “pocosin,” one of those strange words that rolls off the tongue of ecologists, biologists and botanists. Pocosin comes from an Algonquin word meaning “swamp on a hill.” You’ll find pocosins in broad, shallow basins and on broad, flat uplands with sandy humus, muck or peat bottoms. While pocosin refers to a type of wetland with deep, sandy, acidic, peat soils, it also references an evergreen shrub bog community growing in often-wet, nutrient-poor soils, as in bays. Pocosins prove to be near-impenetrable thickets, the thickest undergrowth imaginable.
A visit to a bay reveals a richness of life. You’ll find Venus flytraps at Lewis Ocean Bay Heritage Preserve in Horry County, South Carolina. At least 20 Carolina bays exist on this 10,097-acre preserve. January brings wiregrass and migrating songbirds. March through June, pitcher plants and wildflowers prove dazzling. In the fall, wildflowers such as meadow beauties pop up. You’ll see Venus flytraps, which Charles Darwin called “the most wonderful plant on Earth.” A small, lovely plant, it’s one of the more ingenious predators. Flytraps grow in a narrow 90-mile band from South Carolina into North Carolina where sandy, nutrient-poor soil changes from wet to dry. The leaves, about the size of your thumbnail, trap unwary insects to get what poor soils cannot provide — sustenance.
How does the Venus flytrap catch mobile prey? Its leaves ooze sweet nectar that attracts insects. In the leaf, six trigger hairs lie in wait. A fly lands on a leaf and moves about. Touching the first trigger hair does nothing. Touch the same hair or a second trigger hair, however, and a timer counts down. In 20 seconds, the leaves snap shut. Their outward tips lock together like prison bars. One of nature’s more unusual battles is over and a 10-day digestive period sets in.
Less than 35,000 Venus flytraps remain in the wild and it could be that far fewer live in native habitat. It’s illegal to take Venus flytraps from their wild habitat — and unnecessary. The North Carolina Department of Agriculture’s endangered species division licenses some growers to legally harvest seeds and grow and sell flytraps. People who knowingly buy these plants from poachers contribute to a black market. Another problem flytraps face is loss of habitat. And so this mysterious plant creeps toward extinction. In North Carolina the number of counties growing flytraps has fallen from 20 to 12.
The Venus flytrap by no means is the only deceptive plant in bays. Sundews, nature’s version of flypaper, emit a sweet fragrance that lures insects to tentacles with dew-like glue drops at their tips. Once an insect is hopelessly stuck, tentacles wrap around it. Digestion then begins. The grass pink orchid has no nectar, so it tricks pollinators. Brushy hairs on the uppermost petals resemble pollen-bearing anthers. This duplicity lures insects, which pick up pollen sacs, allowing pollination to occur.
It’s no accident that pitcher plants resemble flowers. That ruse along with an alluring fragrance lures insects to their death so the plant gets much-needed nutrients. Nature is inventive and opportunistic. Spiders build webs across pitcher plants’ openings to capture insects seeking the fragrant “nectar,” which will prove to be their undoing even if they escape spiders’ ambush. As daylight breaks in a bay, grassy zones and pitcher plants glisten with silver films. Spiral webs, funnels, and mesh and sheet webs, silver and sparkly, can be seen everywhere, verifying the large numbers of spiders in bays.
In Carolina bays, you’ll see yellow pitcher plants, lichens, native orchids, bald eagles and red-cockaded woodpeckers. In places, the interior’s thickets of evergreen shrubs create great habitat for black bears and bobcats. Varying water depths, sand rims, and peat mats nurture botanical stars such as water lilies, sedges, red bay, sweet bay, butterworts, gallberry, white- and yellow-fringed and rosebud orchids. Add the rare Wells pixie moss, too.
Nature is peaceful — but not necessarily quiet
Exploring an undisturbed bay is like going to Africa. It is not quiet. It’s filled with cries and calls. Somewhere among the buttressed cypresses a frog sounds like a man chopping wood. What seems to be a large frog sounds like a stack of planks dropping to the ground. A bird looking much like a robin is not, for its call sounds like that of a rainforest bird in the Amazon or Congo Basin. A flash of gold disappears into a pocosin. Orchids and wildflowers spice the air. Zones of grasses lay upon a savanna like a fallen rainbow. Methane bubbles pock mark black waters and a roar akin to a diesel truck coming to life comes from a bull gator. You’ve transported yourself to Joseph Conrad’s “Heart of Darkness.”
People say nature is peaceful and quiet but that just isn’t true. Walking into a Carolina bay known as Craig’s Pond the cry of hawks and the rustle of skinks scooting into cover is constant. Doves coo. The birdsong is ceaseless. Stand in Craig’s Pond’s savanna, and birdsong is a 360-degree experience. It’s the arena of butterflies and dragonflies — big orange ones like biplanes.
As we see, the elliptical and mysterious Carolina bay provides wonderful habitat: pond cypress waters, savannas and dry sand rims support diverse fauna. The bays are often referred to as “islands” high in species richness. Among bay’s residents are flatwoods salamanders, Carolina gopher frogs, egrets, skunks, herons, turtles, snakes and alligators. Sweet gums, maples, buttonbushes, gall berry, sumac, and grasses and sedges live in bays. The wettest bays have open water and floating-leaved aquatic plants like water lilies and tall grasses and rushes.
Preserving undisturbed bays is important, as is the resurrection of disturbed bays. lug a ditched bay and it will restore itself as rains come and go. Bays’ salamanders serve as environmental indicators. As the health of salamanders’ environment goes, so goes man’s.
Man has turned bays into golf courses, soybean fields, campgrounds, parking lots, and laid highways across them. Because of an unfortunate U.S. Supreme Court ruling, the Clean Water Act doesn’t protect Carolina bays as they’re considered isolated wetlands with no inflowing our outflowing streams. Let’s hope this situation will be corrected.
From the days in the early 1980s when the general public first learned of Carolina bays to today, one thing is consistent. Few people know anything about them. Here’s hoping our populace and leaders in government and industry understand just how important Carolina bays are. Spread the word as to how magnificent Carolina bays are as repositories of wildness.
Writer Tom Poland and photographer Robert Clark traveled over 30,000 miles in three states exploring and documenting the phenomenon known as Carolina bays in preparation for their book, “Carolina Bays: Wild, Mysterious, and Majestic Landforms.”
Why Carolina bays are an enduring mystery
Tom Poland and Robert Clark traveled over 30,000 miles in three states documenting the phenomenon known as Carolina bays, the topic of their new book.