Ephemeral wetlands of the Turks & Caicos Islands

Story & Photos By B Naqqi Manco, TCI Naturalist

Walking over the cracked, hardened mud of the flat salinas of the Caicos Islands at the height of the dry season, it is hard to imagine any presence of sweet, fresh water nearby. Even in the cooler parts of the year, the sun burns down without interruption; there is no shade on the salina. A few mangroves and buttonwoods grow contorted, often horizontal and prostrate, hundreds of years old but only inches tall. The harsh sea air wisps through them, gusting in salty jets as the baked mud below reflects the sunlight in its array of saline crystals.

Even when rain does fall here, it will only quench the thirst of the salt enough to allow halophytic plants to grow. They hoard salty water in their succulent tissues and only grow inches high because of the energy they spend on extracting fresh water from the brine. For such small islands, the flatness seems to go on forever—but there looks to be relief in sight. Just below the horizon, a pool of inviting blue lays on the parched land. But the visible heat haze from the land around the pool belies its farce. That pool is a mirage, the bending of light waves that produce an optical illusion of blue where there is none.
But just a bit further north, behind the first ridge, one can sometimes find a genuine oasis—deep, still pools of fresh water reflecting the sky and bringing forth life. But only sometimes, because these wetlands are temporary. Low areas filled with silt collect rainwater in the months following hurricane season, and the saturated, spongy limestone below allows the ponds to stay full.
Life moves in. Eggs of crustaceans and insects and even fish left in the mud begin to hatch. Seeds and rootstocks grow. Sedges and ferns sprout, grasses grow drunkenly tall, falling lax into the pond at its edges, spreading just below the surface. Dominican cattails Typha domingensis spear skyward and push their runners aggressively through the mud, quickly filling shallow corners. Fog-fruit creeper Phyla nodiflora releases its formerly desperate hold on the pond bottom and doesn’t mind swimming around. Guadalupe water-nymph Najas guadalupensis sprouts, able to exist supported by deep water. Normally stiff hatpin sedge Eleocharis bahamensis, endemic to the Turks & Caicos Islands, becomes a lax mat of green hair-grass. Inundated bur-head sword Echinodorus berteroi plants transform their leaves from standing spade shapes to ruffled, flowing blades of kelp. Big-top palm Sabal palmetto and West Indian mahogany Swietenia mahagoni tangle with buttonwood Conocarpus erectus at the ponds’ edges, content with wet feet. Many of these plants are useful to people, who extract thatch for roofs, basketry straw, lumber and even pillow stuffing from these aquatic gardens.
Among the aquatic plants, animals swim and feed. Clam shrimp, bumping along resembling oblong opal lockets, speed through their entire life cycle in just 16 days—one doesn’t know how long the water will remain. Water fleas and copeopods jerk through the water, sometimes clouding it with their numbers. Maligned as they are, mosquito larvae dwell here, but are decidedly few compared to smaller puddles and water collecting in human-related debris—in this pond world, mosquito larvae are on nearly everything’s menu. Elegant, plume-gilled larvae of damselflies and stout, deliberate larvae of dragonflies carefully hunt the mosquito larvae and other aquatic animals amongst the immersed foliage. As soon as they emerge as adults, they flit about, consuming adult mosquitoes, and laying sinking eggs back into the water. Mayfly larvae with frilly gills flashing develop quickly into adults which have precisely 24 hours to find a mate and lay eggs before their natural lifespan expires.
Miniature snails, with flat, coiled shells looking like Middle Caicos fanner-grass baskets, drag themselves through the underwater forest. Inch-long fairy shrimp, with sky-blue bodies and orange tails, jet about looking far more impressive than their cousins sold as pets claiming to be monkeys from the sea. Caddisfly larvae haul their handmade junk-collector shells along with them, simultaneous experts in camouflage and compulsive hoarding. Cartoonish and bumbling, fat water mites paddle furiously with tiny spider legs pulling along a perfectly spherical body far too big for them—and yet, they’re predators, terrifying to water fleas. Backswimmer bugs paddle in fits and starts with their pair of oar-like legs. Busy diving beetles and their dragon-like larvae prowl for smaller swimmers while young giant waterbugs, aptly nicknamed toe-biters or water-scorpions, grab their prey with forelegs modified into spiky calipers, and pierce them to feed with a decidedly unpleasant beak.
On the water surface, drowning flies are collected by skating water striders and whirligig beetles spiraling like obsidian bumper cars. Hunting through are schools of sheepshead minnows, males flashing vibrant iridescent blue to attract mates and warn rivals. They want their territories to be full of eggs, deep in the mud, that will survive until the next post-hurricane rains.
Where once stood a dry, low, meadow dotted with crinkly grass and stout weeds, waterfowl and seabirds forage. They have come inland for this bounty, the herons and egrets as well as the sandpipers, plovers and gulls. Ducks check stock and feed, jumping to the next puddle—white-cheeked pintails with short bursts of flight, West Indian whistling ducks with deliberate overland hikes. Grebes and gallinules build their floating nests, giving their constantly-hungry young a bounty of subaquatic invertebrate protein. Walking along the edge of the ponds, diverse alarm calls can be heard clamoring to one another: the throat-clearing croak of night herons, the gruff squeal of green herons, the multisyllabic whistles of yellowlegs and willets, and the metallic hoots of black-necked stilts. They have all come to hunt in the still, settled water.
Stained by fallen leaves and dead wood, the water begins to take on the hue of Earl Grey tea, preventing algae from taking over. The still surface becomes perfectly reflective. Surrounding trees’ images frame the clouds, mirrored sharply on the water.
As the cooler weather sets in, conditions get dryer. By February and March, the water is nearly gone. By May, the ponds will look no wetter than the salina, and the real mirage of water will have disappeared. The grebes and ducks will have moved on, the dragonflies and damselflies fledged and left behind eggs, the waterbugs affixed their progeny to plant stems. The plants will have replaced their lax leaves with practical, leathery blades, the water-nymph desiccated down to nothing more than dust. Sheepshead minnows, corralled thickly in tiny mud-puddles, will have been finished off by herons and sandpipers, their eggs secure under the mummifying mud.
The dried-down pond mud is rich in nutrients, and weedy herbs will quickly grow up and dominate the newly exposed ground. Historically, some crops were even planted in these “garden ponds.” By the months before the next hurricane season, the ground will turn from cracked mud to baked hardpan to fine dust. Life locked in hibernating capsules under the desiccated silt will wait a year, maybe more if the weather is disagreeable, for the next flood of fresh water. The teeming, tea-stained, mirror waters will only remain a memory, a mirage, until then.

If you want to visit TCI’s ephemeral freshwater wetlands, drive along the King Road in North Caicos between Whitby and Bottle Creek, keeping a lookout for flashes of water in the bush beside the road; or hike around Kew’s oak bottoms. In Middle Caicos, a walk along Garden Pond Field-road near Lorimers will find such ponds. Be sure to cover up and apply repellant, as some of the most common citizens of the freshwater wetlands are mosquitoes!