When a Tree Falls in the Forest …

Today’s slide show: Images from Corcovado. Today’s audio: Two platform survivors talk about their overnight. Today’s video: Ascent into the trees, and the view from the platform.

CORCOVADO—One of the good things about being in a bona fide “eco-location” like Corcovado National Park is that you don’t have the luxury of guilt. If you’re lolling about the beach on a poor Caribbean island while starch-shirted locals serve you Kahlúa ‘n’ cream, well, you should be lubricated with as much guilt as sun lotion; it’s only seemly. But if you’re in a tent camp picking blood-drunk ticks off your thighs and really, really missing hot showers and noticing that your toenails are starting to look like weasel claws, well, then, you’re free! You are not a spoiled gringa. You are doing your job. You are loving nature, and nature, ever gracious, is loving you back.

Not long ago eco-tourism was served up as the perfect solution to a terrible dilemma. The people with the most money lived in places with the least amount of untouched wilderness, while those in the places still blessed with bio-bounty were impoverished. How could we exchange the two classes of wealth and so preserve the world’s remaining biodiversity, which, who knows, we Homo sapiens might actually need at some point, and even prefer over another Sears-anchored shopping mall? Answer: Seduce the rich tourists to the poor nations with the promise of showing them what they’re missing. Turn a golden-headed tanager into a golden-egged goose.

Dreamy though that plan sounds in theory, in fact not every wilderness area makes for effective eco-tourism. As Bill Weber of the Wildlife Conservation Society explained to me, you need a few things to make a nice place to visit. You need dramatic flagship species, like the mountain gorillas of Rwanda, which, before the genocidal Rwandan civil war, were a huge tourist draw; or the monkeys, tapirs, toucans, macaws, anteaters, coatis, etc., ad Darwinitum of Costa Rica. You need reasonable social and political stability, a definite Costa Rican draw since the country abolished its army in 1948, the same year, incidentally or not, that Costa Rican women won the right to vote. And you need mountains or similarly elevated ranges with great views. It’s not much fun to be slogging through a tropical forest where you’re stuck in the lowlands and most of the action is in the canopy, as I remember all too well from my visit to the Venezuelan rain forest. We hardly saw anything beyond docents of the arthropod order. But Costa Rica has lots of mountains and lots of high places, which helps to explain its unusual success as a vacation destination.

Today we got very high indeed, in altitude as well as on pura vida—pure life, a common Costa Rican interjection. Should you be casting about for an alternative to “Cool!” or “That’s awesome!” why not try “POO-ra VEE-da.”

Esteban Erichsen demonstrates the canopy harness

First we took a nice bracing hike 600 feet up from the Corcovado Lodge—a tent-camp right on the beach—accompanied by architecture student and sometime nature guide Esteban Erichsen, who is spider-monkey thin and Frida Kahlo browed. Esteban is my kind of guide, shamelessly free-associating and anthropomorphizing. He points out to us the red-capped manakin’s “yellow underwear.” He scoops up an anole lizard and talks of the male’s expandable vermilion throat pouch as the “big red tie he wears on a date.” Hearing a distinctive whistle, Esteban tells us it’s the famous Costa Rican taxi bird. After the hike, we ascended 120 more feet up a tree and onto the famed Corcovado canopy platform. What do I mean by “ascend”? I mean, put on a helmet, a frankly unflattering doggy harness, and a giant red diaper, and get hoisted up the tree by pulleys. Whee! It’s a lot more fun than changing diapers, I’ll tell you that. Though maybe Karla won’t: She’s done the ascent many times, and still she cursed bilingually as she rose.

From the platform, you can look out way across the canopy, the uppermost layer of the forest, where most species spend most of their time: the primates, the birds, the poison dart frogs, the two-toed sloths, the three-toed sloths, the busy, bulging-bellied tiger ants. Corcovado has some of the tallest trees in Costa Rica, and some of the most virginal forest. It seemed that no two trees in view were of the same species or the same shade of green. I wondered how that one modest bit of the visible electromagnetic spectrum between yellow and blue could be subsectioned so finely. Tropical rain forests are known for their astonishing biodiversity, of course: many many species, with relatively few members of each species managing to elbow their way into the room. Temperate regions, by contrast, have fewer species but more representatives of each—more oaks, more maples, more gray squirrels. Why are tropical rain forests so diverse? Why are no two creatures like each other? I don’t know; go ask your mother. I’m not just being coy here. The precise reasons why diversity reigns in the rain forest remain mysterious.

Up she goes: Natalie leaves the ground, bound for the skies

Yet certain themes play themselves out again and again. Parasitism, for one, as exemplified by the strangler fig. The strangler begins life as an epiphyte on a host tree, hanging in mock innocence on a branch and letting its woody roots start growing soilward. The roots wrap around the host trunk and grow thicker and thicker, as does the foliage of the fig plant above. The fig roots look to be suffocating the host, but really the crown is the killer, as it outcompetes the host leaves for photosynthetic lifeblood. Eventually, the host tree dies and is hollowed out by termites, leaving the lacey fig supermatrix standing its ground. Sooner or later, though, the fig will start tottering too and be attacked by termites and battered by woodpeckers, until the whole towering mass crashes to the ground. At which point all the understory foliage, eager for its chance in the sun, will seek to fill the vacancy. Sunlight is at a premium in Corcovado, and when a tree falls in this forest, you can be sure that everybody hears it.

Today, we also heard a sound of real joy, when Karla first laid eyes on a turquoise cotinga, a small bird with a dazzling iridescent blue body. She’d never seen one before, and that is unusual for a woman who has spent the past 12 years studying the bioscene of Costa Rica. Karla couldn’t wait to tell her husband: Guess what, dear. I saw turquoise cotinga, and you haven’t! Life is good, life is awesome. Pura vida.

Things to know before you go to Costa Rica.