Masked by stinking anaerobic mud, fuggy heat, clouds of mosquitoes, and acre upon acre of flooded forest, mangroves are as mysterious as they are vital to our coasts.
Paddling south from highway 41 along the Turner River, the South Florida scenery quickly turns positively prehistoric. Schools of mullet and yard-long gar glide below my kayak, while black willows and pond-apple trees lean out from the banks of the thin, tea-colored waterway. Around a bend in the river, a dark, scaly sentinel lies warily at the water's edge; luckily my guide, David Harraden, who has been paddling these waterways for more than 30 years, and I ease past the 12-foot alligator without incident.
A few further turns and the meandering river reveals a different forest than our launch site's freshwater cypress swamp. A crazily arching latticework--the distinctive aerial prop roots of red mangrove trees--sprouts from the muck and weaves a near-impenetrable buttress comprised of boughs and branches. Harraden, an avid outdoorsman who owns an eco-hotel in nearby Everglades City, ducks into a tiny tunnel boring through the thicket, a passage that's also used by gators and river otters and serves as a flyway for belted kingfishers and egrets.
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The corridor is too narrow to paddle, so we pole and pull our way along, scattering water striders and shaking dew-covered spider webs. In the rising heat of a late spring morning, the shade provided by the mangrove forest makes things perceptibly cooler than out on the open water. This labyrinth lasts a quarter-mile, maybe longer; on such a swampy slalom course, it's impossible to know. The songs of unseen birds--the shrill whistling of ospreys, the big buzz of tiny palm warblers--fill the still air. Only shards of sunlight penetrate the ancient canopy's tangle of limbs and roots. I half-expect to see dinosaurs. Wait, that gator does count.
"It's a mystical place,'' says Harraden, in the hushed, reverential voice of someone speaking inside a cathedral. "The more you immerse yourself, the longer you stay, the more beautiful it becomes.''
Admittedly, the beauty to be found here amid the stinking anaerobic mud and fuggy heat and clouds of mosquitoes is subtle. This landscape has none of the undeniable drama seen at many other nature destinations, from the splendor of a soaring California sequoia grove to the Crayola colors of Belize's barrier reef. Yet these humble mangroves are freakishly resilient, with an ability to survive, and even thrive, in a harsh tidewater environment that would kill any other tree. A closer look at this landscape, with its flocks of wading birds and brigades of scuttling crabs, its schools of juvenile fish and gantlets of lurking alligators, only hints at their vital value as nursing, feeding, spawning, and sheltering grounds. Mangroves also stabilize coastlines, filter sediments, and mitigate storm damage.
The three different types of Florida mangroves--red, black, and white--have each developed a magic alchemy for surviving in salty, oxygen-depleted soils created from a soggy mix of sand, silt, clay, and detritus. Closest to shore--and sometimes even erupting in the midst of shallow bays--red mangroves (Rhizophora mangle) are distinguished by stiltlike prop roots that provide stability in the face of wind and tide. The roots are also pocked with small openings called lenticels through which oxygen moves into and out of the plant. Salt is expelled at the roots as well as by the leaves, which are then dropped. Black mangroves (Avicennia germinans), which typically grow on slightly higher ground than Rhizophora, feature clusters of pencil-sized aerial roots called pneumatophores that function like snorkels to supply oxygen to the plant during high tides. These trees also excrete salt in visible crystals on their leaves. White mangroves (Laguncularia racemosa), which grow above the high-tide line and usually have no need for specialized prop or air roots, have a gland at the base of each leaf that expels salt and sugar.
These adaptations are why mangroves flourish along tropical and subtropical shorelines and tidal estuaries. They grow in more than 120 countries and territories, from Indonesia, which has one-fifth of the planet's estimated 37 million remaining mangrove acres, to the tiny South Pacific island nation of Nauru, which holds just five acres. The Bengal tiger's last stronghold is also the biggest mangrove forest in the world, the Sundarbans of India and Bangladesh.
North America's most impressive mangrove forest is found along Florida's southwest coast, extending from Flamingo, at the very tip of the peninsula, all the way to Marco Island, roughly 100 miles to the northwest. Known as the Ten Thousand Islands, this maze of mangrove islets, tidal creeks, and shallow bays has long been a haven for wildlife, including large populations of wading birds and a viable population of American crocodiles, listed in Florida as a threatened species. Rumrunners and dope smugglers have also used its bewilderment to their advantage.
A handful of communities make a more legal go of it with sportfishing, airboat rides, and the public's appetite for stone crab. In this half-drowned world, boats are necessary. The vagaries of tide and weather dictate movement. Everyone is at the mercy of heat and bugs. It's a hard-knock life, even for scientists studying the biggest wilderness east of the Mississippi.