Mangrove Man

Day 45: 190 Pounds

 

Dying feels odd.

That may be an overly broad statement. Some demises, I assume, are awful. Others may be peaceful or terrifying or even pleasurable. I can only speak to my own half dozen (give or take) brushes with death, so take my description with a grain of salt.

Not all near death experiences are made the same. Rather, they lay on a continuum. At the least deadly end of the spectrum are “I’d better not fuck up” (IBNFU) situations. They include the time I held a live M67 fragmentation grenade with the pins pulled out while a nervous 82nd Airborne instructor looked on wondering if I was about to blow myself, or him, or both of us to hell. Or when I scrambled up a cliff face with a broken shin I could quite literally feel separate and rejoin with every step. I don’t necessarily count these as capital “N”, capital “D”, capital “E” Near Death Experiences, but they provide a handy minimum criterion, as one slip or miscalculation would spell certain doom.

Toward the middle of the killy continuum are “that should have ended me” (TSHEM) situations. These are instances when, if things pan out slightly different–a milimeter to the left or right, a millisecond before or after–I’m a goner. Representative samples include the two separate times (aged five and 16) two different German shepherds mauled me. Another example was when I flew 15 feet through the air on a mountain bike before landing square on my neck, smashing my helmet in the process.

Finally, at the deadliest end of the spectrum is “death as a process” (DAAP). Sometimes, expiration isn’t instantaneous, but a well-documented, step-by-step shutting down of one’s biological machinery during which I’d damn well better do everything in my power to stop or I will shuffle off this mortal coil. Almost drowning in Australia’s Great Barrier Reef was one such experience. 

It’s June 2018, I’m dying, and it feels very, very odd. 

The greatest dangers I face in the mangroves are not crocodiles, poisonous snakes, spiders, or crazed squatters with machetes. The biggest risk I run isn’t stalking me from the water, creeping silently through the undergrowth, or writing manifestos in a lean-to. It’s the most blatantly obvious object in my surroundings: the sun.

Heat kills quickly in South Florida’s mangrove forests and does so in brutal fashion. In essence, it cooks your brain.

The first step is heat exhaustion. In the mangroves, especially during the summer, the humidity routinely peaks above 90%. Sweat can’t evaporate from your skin, which doesn’t allow heat to transfer from your body into the atmosphere. As the ambient temperature shoots above 100 degrees Fahrenheit, it feels like you’re in a boiling pot with the lid on.

It is my 45th day cleaning the mangroves, my first summer out there, and I spend the afternoon collecting 190 pounds of trash. I have no idea what I’m doing. In that heat, my heart rate easily rises above 155 beats per minute (the equivalent of a multi-mile run in cooler temperatures) without moving a muscle. There are ways to navigate the mangroves–slowly, methodically, with periodic pauses–that mitigate the risk of pressure cooking my cerebellum, and I’m doing any of them.

I collect four 42-gallon bags full of trash into a pile in front of my GoPro and try to sound triumphant about just passing the 5,000-pound mark, but I’m in deep trouble.

I have to do take after take after take because my speech is slurring. My fine motor skills disappear. My fingers feel enormous and unwieldy, like pool noodles attached to my palms. I have a hard time holding objects or removing my knife from its scabbard on my hip. I can barely stay upright. The horizon swings wildly. It feels like the Greek goddess of war and wisdom is smashing her way out from inside my skull. Most worryingly, my vision is blurring. Blackout curtains roll in from the sides. 

I am moments from heat stroke, at which point I will collapse and probably die. I have no cell phone reception, no way to cry out for help, and no one knows where I am. In layman’s terms, I’m screwed.

It’s not how I want to go, but it’s also exactly how I want to go. If I have my way, upon my death, my naked body will be laid in a tidal pool deep in the mangroves to be picked clean by crocodiles, turkey vultures, mangrove snapper, land crabs, and raccoons. It’ll only take a few weeks before all that is left of me is a scattering of sun-bleached bones. My only hope is that my leering skull be placed prominently in the crook of a tree to terrify would-be litterers. 

Luckily, I remember enough of my combat first aid training to recognize the symptoms. I lay on the sand, place my hat over my face, lift my legs on a stump, and wait. Hermit crabs scuttle by to check if I’ll be their next all-you-can-eat buffet. Black vultures circle a thermal overhead. The sun sinks slowly behind Key Biscayne and into the bay. The temperature cools, and I don’t die. But, sunset is also when stinging insects are most active, so nature gives me one final kick in the ass in the form of hundreds of mosquito bites as I stumble toward my bike.

The headache doesn’t dissipate for two days. My entire body aches for a week. But I don’t die.

I return the following week. And the next one. And the one after. I’m still going, 200 days and 43,000 pounds of trash into my weird little hobby.

What is a Mangrove Forest?

A person unfamiliar with a mangrove forest might take a good look at one and conclude it is a broiling, bug infested morass of foul smelling, soul and boot sucking mud no rational person would want to experience from any closer than a chartered boat anchored a mile offshore–and they wouldn’t be wrong. 

The mangroves aren’t for everyone, nor should they be. Modern humans evolved in open African savannas and woodlands, so the habitat to which I’ve dedicated my life is deeply alien to most people. The mere act of traversing it can be disorienting and frustrating. When leading group cleanups, I often have to wait for participants to catch up because they instinctively attempt to walk in straight lines. There are no straight lines in the mangroves. Traveling from one point to another is a meandering, acrobatic experience that involves constantly calculating the ground’s firmness as one ducks, weaves, climbs, crawls, and doubles back through a verdant tangle of roots, trunks, and branches that can restrict visibility to 10 feet. With no landmarks or terrain features, someone lacking a compass, GPS device, or knowledge of how to utilize the sun for wayfinding can find themselves walking in endless circles.

But a mangrove forest is so much more than a quagmire. It is a landscape in perpetual transition. Channels open and close. Centuries-old trees the size of mid-rise apartment blocks fall over and die to be replaced by thousands of seedlings all competing to fill the same patch of sunlight. Sandy grasslands transform into waterlogged strands of man-sized saplings packed so densely as to be impassable.

Mangrove forests are tidal brackish water ecosystems residing on the blurriest possible frontier between land and sea. Water levels rise and fall dramatically twice a day. Yellow rat snakes slithering around prop roots at midday replace balloon fish darting around those same roots through three feet of water at sunrise. 

Indeed, a patient observer can watch the tide fluctuate in real-time. Dark striations on the roots and trunks demarcate their maximum height. Someone lost in the mangroves can simply walk either with (when the tide is falling) or against (when it is rising) the flow of water to the ocean, where they are more likely to find rescue by boat.

The mangroves also change drastically on a yearly cycle. Twigs and branches cracking underfoot during South Florida’s winter and spring dry season float atop a knee-deep muddy plane the consistency of lentil soup during the rainy summer and fall months. October’s and November’s king tides cover the forest in several feet of cool, crystal clear water, even at low tide. Hurricane season augurs the most sudden alterations, as tons of sand pile overnight into new dry ground or are swept to sea, carving out deep tidal pools that soon brim with snapper and bonefish.

The planet is ringed by a belt of mangroves roughly spanning the latitudes of 25 degrees North and South. Their range is limited to the subtropics because even a few hours of frost exposure can kill most of these trees. However, as global temperatures warm and sea levels rise, mangroves’ territory is expanding north, south, and inland.

Depending on which scientist you ask and how pedantic they want to be, there are anywhere between 54 and 80 mangrove species found in 118 countries. They cover an area of 77,000 square miles, 42% of which is in Asia, 26% in North and South America, 21% in Africa, and 12% in Oceania. This book, however, focuses on the mangroves’ northernmost Western Hemispheric foothold in South Florida because, well, that’s where I pick up trash.

The Mangroves

What is a mangrove?

First and foremost are red mangroves (Rhizophora mangle). Of Florida’s three species, they reside closest to the coast. Their most notable feature is the reddish-brown tangle of prop roots extending from their trunks and branches into the sand below. Beyond granting them the appearance of walking across the surface of the water, they supply oxygen to the trees’ underground roots and make them the linebackers of the plant kingdom. Prop roots are living flying buttresses. They brace and support their tree as it grows up to six stories tall and 30 feet wide.

Red mangrove prop roots allow them to survive one of the greatest calamities in the natural world: a direct hit and from a Category 5 hurricane. As this monster plows across the ocean, its low atmospheric pressure creates a storm surge, a mound of water that can reach 20 feet in height by the time it slams into a mangrove forest. Red mangroves are in the very front rank, taking the undiluted brunt of the attack. Smaller trees are completely submerged in water. Yachts, refrigerators, tires, car batteries, lobster traps, and tons of humanity’s accumulated detritus barrel into tree trunks like wrecking balls. And yet, once the waters recede, a healthy red mangrove forest can shrug off the storm. Its defoliated canopy grows back in a year, hundreds of saplings replace fallen trees, and the only evidence of the biblical violence inflicted is the millions of new pieces of trash spread a quarter mile inland. 

The roots are surprisingly powerful, as they evolved to break apart limestone bedrock in search of minerals. That means they can drill straight through rubber, plastic, aluminum, and, eventually, even steel. I saw the remains of a pickup truck engine strewn across the mud after prop roots grew into its crevices and pulled it apart. Mangrove forests are one of the world’s most caustic environments, not just due to the corrosive combination of water, salt, bacteria, and heat, but because the trees themselves rip manmade objects to shreds. Given enough time, nothing survives the mangroves intact.

Some readers may be familiar with the concept of the “Woodwide Web.” For much of the 20th century, the scientific consensus stated that forest trees reside in a hyper-Darwinian landscape where they do just about anything to outcompete each other for sunlight, minerals, and space. However, over the last few decades, arborists noticed that tree roots are interconnected by a matrix of fungi (mycelium). Trees under attack by pests or pathogens can use the fungal network to send out chemical alarms, allowing the entire forest to preemptively produce countermeasures. Even more astonishingly, this biological internet allows parent trees to deliver sugars to their offspring, granting them a greater chance of survival. There are even documented instances of trees of different species sharing resources with weakened neighbors.

I once tried to use a shovel to remove a car bumper buried in a red mangrove forest. It didn’t go well. The experience was like trying to dig a hole in a mattress or an enormous sponge. After an hour of watching the shovel blade literally bounce off the sand, I gave up. The roots of Florida mangrove species only grow about 30 inches underground. Such a shallow root system would normally make trees unstable and liable to fall over, especially when confronted with powerful winds and storm surges. However, a study published in Communications Biology found that mangrove roots are capable of something extraordinary. 

Unlike their counterparts on dryer, higher ground, the fiber optic cables connecting mangroves’ Woodwide Web aren’t fungi. Rather, they seem to use a different mechanism to achieve the same end in the form of root grafting, a process through which different trees’ underground root systems physically fuse together. This allows them to communicate and share resources but, even more astonishingly, it creates a forest-wide support superstructure that makes it incredibly difficult to knock over any single tree. Each individual supports its neighbor, locked together in a perpetual embrace, standing against nature’s most destructive forces like a shield wall.

Shifting our gaze up from the sand, a red mangrove’s prop roots arc from a smooth, gray trunk with reddish-brown mottling. Depending on its environment, a mature tree can appear as a low shrub or grow as tall as 65 feet–an incredible accomplishment in nutrient-poor anaerobic soil. More prop roots descend from the branches which, once anchored in the sand, can take on the appearance and thickness of additional trunks, further reinforcing the tree’s legendary stability. 

Red mangrove leaves are smooth, elliptical, and between three to seven inches long. The top of the leaf is dark green and shiny while its bottom is duller gray-green. A waxy coating–a trait found among all mangrove species and many other coastal plants that helps them retain water–gives the leaf a leathery texture. 

Tiny yellow flowers at the ends of the branches bloom throughout the year and produce propagules, yet another incredible adaptation that allows mangroves to thrive in a hostile habitat. These curved, green, cigar-shaped doodads are seeds, only cooler. They hang from branches by a narrow, tapered top that widens to a thicker bottom. Unlike most other plants, however, they germinate while still attached to their parents.

At the risk of further anthropomorphizing my favorite tree, this evolutionary quirk has been described as the plant version of live birth. It gives propagules a head start when they mature and drop into the water below. Global currents can then carry them thousands of miles across oceans. They are naturally buoyant, though their shape and denser bottoms means they float vertically with their tops bobbing at the surface until they slide, rightside up, into the sand of their new homes, ready to immediately sprout trunks, roots, and leaves.

Moving inland from the coast and onto slightly higher ground, one finds black mangroves (Avicennia germinans). Their roots are usually exposed at low tide, and what roots they have! It’s difficult to misidentify a black mangrove because, surrounding the trunk over an area up to 30 feet wide is a field of what appear to be gnarled witch fingers poking out of the ground. These year-round Halloween decorations are called pneumatophores, or “air-breathing roots.” They act as natural snorkels, allowing the tree to exchange gasses with the atmosphere even when partially underwater.

A black mangrove’s trunk is dark brown, shading to black (hence the name). It is also generally thicker and more gnarled than a red mangrove’s. Growing up to 65 feet in height, it lacks prop roots extending to the ground. Its leaves have a similar coloration to a red mangrove’s, though they are more oval and slightly smaller. Upon close inspection, one can see crystals dusting the tops of those leaves. This is how the tree excretes excess salt from its brackish water source. For the curious, you’re damn sure I’ve licked my share of black mangrove leaves and can indeed confirm they are salty. At the end of its branches, one finds inch-long, tear-shaped propagules. Like their red mangrove counterparts, they also float and germinate before dropping from their parent.

At last, we come to the white mangrove (Laguncularia racemos). It can be found residing above the daily tide’s highwater mark. One may be tempted to write it off as the weakest mangrove species, unable to weather life on the tidal frontlines, but that would ignore the harshness of the environment in which it evolved to thrive.

White mangroves are perfectly happy to grow straight out of sand. The thing about this substrate is that it drains very quickly. Even during South Florida’s wet season when it rains practically every day, the water rapidly sinks into the water table beyond the roots’ reach. Furthermore, months can pass during the dry winter season without more than a rare rain shower. Nevertheless, white mangroves’ habitats are often exposed to tropical storms and king tides, meaning that the trees have somehow adapted to both prolonged drought and regular flooding.

White mangroves don’t sport either prop roots or large pneumatophores. Their trunks are light brown and can grow up to 40 feet high. Their bark’s high concentration of tannin led to it being used to treat dysentery, fever, wounds, scurvy, and ulcers. The leaves are small (between one and five inches long), oval, and light green. At the base of each leaf is a pair of sugar and salt-secreting glands called nectarines that attract insects. Tiny white flowers bloom year-round in clusters found at the ends of branches. Once pollinated, they transform into buoyant oblong pods about an inch long. 

Red mangrove forests are easy to identify because the only sizable trees growing in the area are, well, red mangroves. Other potential competitors wisely cede this salty, waterlogged, oxygen-depleted, mineral-poor, storm-lashed environment in favor of saner places to live. However, one will be immediately disabused of the notion that these forests are monocultures upon simply glancing up.

Everywhere one looks–the prop roots, trunks, and branches–is colonized by bromeliads. These relatives of the pineapple put on a hell of a show, breaking the mangroves’ dark green and rust-colored monotony with a riot of crimson, purple, yellow, and pink flowers. Bromeliads derive all their nutrients and water from the air and do not hurt their host trees. They also form their own micro-ecosystems populated by insects, crabs, lizards, and snakes. 

Beside a host of other air plants like orchids, ball moss (think fuzzy, gray globoids straight out of Studio Ghibli), and draping curtains of Spanish moss, even black mangroves don’t have many terrestrial neighbors other than their red and white cousins. However, once you enter white mangrove territory, the biome begins to change.

The Neighbors

Mangrove forests bleed and meld into other ecosystems–no clear delineations, no straight lines. Patches of high ground deep in the swamp are claimed hardwood groves. A constant southward freshwater flow from Lake Okeechobee transitions coastal mangroves into the Everglades’ endless sawgrass expanse. 

Much of Florida’s undeveloped shoreline abutting the mangroves is composed of untidy beaches filled with Native shell mounds, driftwood, and slowly rotting seaweed worlds away from the Instagramable sterility found among South Beach’s kilotons of imported Bahamian sand. In the summer, sargassum, manatee grass, and turtle grass pile into drifts several feet high. Trip over any one of these mounds and you’re liable to kick up beetles, crabs, flies, scorpions, and hundreds of tiny jumping crustaceans called sand fleas. Raccoons, ibis, terns, herons, and egrets love nothing more than picking through this invertebrate smorgasbord. 

Above the high tide line, loggerhead, green, and hawksbill turtles dig their nests. At about the size of a vinyl record, endangered Kemp’s Ridley turtles nest in this zone. On the other end of the spectrum, leatherback turtles clocking in at eight feet long and 2,000 pounds also lumber ashore to lay their eggs. While running down Key Biscayne’s Atlantic coast one night, a leatherback and I both screamed (its was more of a sharp guttural grunt) when we almost collided, and not a soul on Earth can blame me because, I swear, it was like seeing a Volkswagen-shaped dinosaur emerge from the ocean.

Sand dunes rise 20 to 30 feet above the beach. However, Jonathan Dickinson Park’s largest dune towers 86 feet above its surroundings, making it South Florida’s tallest natural point. Closest to the ocean, one finds pioneer plants like sea oat, railroad vine, and sandspur (the latter produces seeds that terminate in barbed spikes, making them the beach equivalent of tiny landmines for the incautious or unshod). These plants’ deep roots anchor the dunes, stopping their sand from being scattered by the wind and surf.

The vegetation grows larger on the dunes’ backsides. South Florida’s subtropical climate might seem an odd place to find prickly pear cactus, but they love the sandy soil. Having accidentally kicked more cacti than I’ll admit, I’ve pulled enough needles from my toes to keep a permanent lookout. Saw palmettos produce dense bunches of chest-high fronds that slice anyone foolish enough to walk through a grove in shorts. As if that weren’t enough to worry about, cordgrass grows in spherical bunches as tall as a person. Its leaf blades roll into needlelike points sharp enough to take out an eye or pierce skin, even through clothes and gloves.

Sea grapes’ large, waxy leaves block the plants behind them from exposure to ocean spray. Their shallow root balls mean they are easily knocked over by hurricanes, but they can resprout new trunks without skipping a beat. Sabal palms (also known as cabbage palms), Florida’s iconic state trees, have deep root systems, flexible trunks, and aerodynamic fronds that allow them to weather the strongest storms. Their hardiness makes them ubiquitous across the Sunshine State’s pine rocklands, hardwood hammocks, grass prairies, and Everglades tree islands. 

And, everywhere you look, flowers! Moonflowers’ fragrant blooms perfume the dunes when the sun sets. Morning glories grow in a vibrant palette of blues, purples, pinks, and reds. Beach sunflowers look just like miniature versions of their larger inshore relatives. Endangered monarch, Atala, Miami blue, and Schaus’ swallowtail butterflies flitter over the blossoms. Mixed into this natural perfumery, one smells sea lavender and baby sage on the wind, their aromatic notes turning the landscape into an outdoor spice pantry. 

We’ve now traveled far enough from the ocean to approach the hardwood hammock. White mangroves often reside along hammocks’ outer borders, along with buttonwood. Sometimes referred to as “gray mangroves,” these trees are not true mangroves, but a close relative. Their trunks are deeply gnarled and the branches terminate in small, green, leathery leaves with pointed tips. Silver buttonwoods’ leaves are covered in fine, silky hairs that protect against sea salt and water loss. They give the trees a beautiful pearly complexion and, when the rising sun hits them just right, entire groves glow.

Within the hardwood hammock,the trees are taller, the underbrush denser. The thick canopy muffles the waves and smothers the forest floor in a half-gloom, even at midday.  Gumbo limbo’s papery bark peels off in red patches, giving it the nickname the “tourist tree” due to visitors’ predilection for burning in South Florida’s merciless sun. 

The undisputed queens of this habitat, towering high above other flora, are hardwoods like mahogany, red maple, and strangler fig. The latter has one of the hammock’s most dramatic transformations. Its fruit is consumed by birds who then deposit seeds in droppings as they fly through the canopy. After a seed germinates, it extends roots down the length of the tree’s trunk toward the soil. More roots follow, completely encasing the host, outcompeting its roots, and killing it. Though brutal, the strangler fig’s hollow trunk provides shelter and its fruit are an important food source for birds, bats, and many other native animals.

Live oak earns its moniker because it, unlike its temperate relatives, doesn’t shed its leaves or enter a hibernatory state in winter. These behemoths can grow up to 80 feet tall and 120 feet wide, each sprawling limb a world of its own, home to thousands of ferns, bromeliads, vines, palms, and uncountable insects, reptiles, amphibians, birds, and mammals.

Closer to the forest floor, ground cherries sprout in the fall, tangy and saccharine. Wild coffee’s bright red berries bunch at the ends of their stems. Though edible, they don’t contain caffeine. Sabal palms, sea grapes, and saw palmettos, all of which have edible berries, are also common. My favorite hammock fruit, however, is coco plum. Thick bushes with delicate oval leaves produce purple and white berries the size of grapes. Because they have not been domesticated, their large seeds are covered by a thin, subtly sweet layer of pulp. Come summer, I’ll happily eat dozens at a time.

Not all hardwood hammock trees are so benign. Poisonwood sounds ominous because it is. You can identify this relative of poison ivy and poison sumac by its droopy leaves and oily, black sap oozing from its trunk and branches. Though a critical component of the hardwood hammock ecosystem, providing food for native fauna and helping anchor the soil, poisonwood and I have an unhappy history. 

I’ve been exposed to poison ivy many times. I itch for a few days and it goes away. Poisonwood tortured me for weeks. I didn’t even touch the thing. I simply cleaned an abandoned camp under a poisonwood grove. It rained, the water washed off the leaves, landed on my clothes, and that was enough to set off the worst allergic reaction of my life. 

My entire body broke into unbearably itchy weeping sores that kept me up all night. Draining the pus only brought temporary relief as the sores spread across my back, abdomen, neck, arms, and legs. The handful of antibiotics I received after a skin infection misdiagnosis just gave me diarrhea. Only when a dermatologist handed me a prescription-strength steroid did the sores finally dissipate.

In terms of toxicity, however, manicheel is in a league of its own. Dubbed “the tree of death” by Spanish conquistadors, contact with or even proximity to any part is extremely dangerous. Manicheel is on the brink of extinction in Florida but can still be found in the Upper Keys’ and Southern Everglades’ hardwood hammocks. Growing up to 50 feet tall, its cracked grayish trunk and finely serrated leaves produce a milky-white sap that blisters skin and causes blindness. Its fruits look like tiny, bright green apples that supposedly taste sweet, not that you’d have much time to enjoy one before catastrophic internal hemorrhaging kills within hours. Native Calusa warriors tipped their arrows with the sap, which is how Ponce de León met his end after they shot him in the thigh as he pillaged his way across South Florida in the 16th century.

Traversing an undeveloped hardwood hammock, one is soon reminded that Florida’s history began millenia before the first European reached the Western Hemisphere. Rising from the otherwise flat terrain, like silent sentinels, enduring testaments to the cultures and people who built them, are the midden mounds. Built by the Calusa and Tequesta, South Florida’s original inhabitants, these 20 to 30-foot-high hillocks constructed of shells, bones, rock, and soil are thought to have served as ceremonial centers, burial chambers, and territorial markers. Infuriatingly, hundreds of irreplaceable sites were leveled by developers and topped by single-family homes, their contents used for road building material.

On an even grander scale, the Calusa’s most stunning architectural achievements are the shell islands they built throughout their territory. These artificial islands like Watson’s Place and Chokoloskee cover multiple square acres. Mound Key, the largest shell island in Florida, was the Calusa’s capital town. It rose more than 30 feet above the surrounding Cape Coral estuary and covered an area of 125 acres. 

The first midden mound I encountered struck me dumb. It seemed an impossible structure in an impossible location, proof that I am a transitory visitor in a place that was home to advanced cultures thousands of years before I ever stumbled upon their monuments. Then I realized the mound was the first in a line stretching hundreds of meters. My legs buckled and I sat down, the weight of scale, scope, and time far heavier than any bag I ever carried.

Now surrounded by mangroves and overgrown by gumbo limbos, wild coffee, poisonwood, and strangler figs, I remove the empty beer bottles, Styrofoam, and plastic bags that litter these priceless surviving cultural sites. I also keep them hidden from those who may damage or desecrate them. It’s the least I can do for those who built them.