Wednesday, March 31, 2010

Getting There.

I had been walking for hours, running low on water, and was surrounded by a dense and foreboding jungle when I realized I may have underestimated the hike through Corcovado National Park.

Earlier that morning my group and I had loaded ourselves into two modified pickup trucks to travel to Corcovado’s Los Patos Ranger Station, our gateway to one of the largest remaining tracts of pacific tropical rainforest in Central America. There are several ranger stations within the park and the one where we’d eventually be staying was an 18 km (about 11 mile) hike from Los Patos. But just getting to this border station where we’d start our hike took some work.

We drove for only a few minutes before we left behind all sign of the small town where we had spent the previous night. Sitting on makeshift benches in the bed of the pickup, we struggled to grab a hold of the truck and not each other as we tilted mightily over the rocky road. Rivers ran alongside us and crossed the gravel frequently; facing backwards, my only warning we were about to plunge into the rushing water was the alarmed expressions of those in the cab of the truck following me.


The jungle rose precipitously along each side of the road, growing on steep hillsides towering above us. Toucans flew through the trees, disappearing behind the tarp covering the back of the truck. I didn’t know it at the time, but we were driving alongside a reserve for the indigenous Ngöbe (Guaymi) people.

Upon arriving at Los Patos, we signed in and started the long trek. Only a few minutes into the hike, we came to our first stream crossing. Although I had already convinced myself this day would be a personal endurance test and didn’t anticipate a comfortable experience, I thought I’d be able to enjoy the hike a little bit longer before my boots became soaked. After a brief hesitation, I plunged in. It turned out to matter little, as the rest of my clothes were soon as wet as my boots, drenched in sweat as I parted the humid air along the path.

The trail was steep early and my legs protested as I hauled myself up muddy hills, treading carefully to avoid slipping on wet leaves. As the path gradually leveled off, I took my time and strolled leisurely, pausing frequently to peer through the trees in the hopes of spotting a prowling jungle cat looking back at me or perhaps an eyelash palm pitviper coiled within the nearby vegetation. Quickly, I was at the back of the pack.


Hours later I was tired but in good spirits when I noticed some flagging that had been left behind by those who had hiked through earlier; I grabbed it when I saw there was an accompanying note. With the flagging in my hand I stared at the words in front of me as sweat dripped off my forehead and onto the ground by my feet. After hiking for so long, I had assumed I was at least coming close to approaching the Sirena station where we would be spending the next six nights. The note however, indicated otherwise. Those who had left it had passed through a full hour and a half earlier, that part I could accept. What I couldn’t believe was that the note indicated there was “only” 11 more kilometers to go. Eleven kilometers? I did the math in my head. I had only completed roughly a third of the hike.

Slowly and instinctively, I checked how much water I had remaining. About half. I knew I would run out before I got to Sirena if I continued to take my time. Saying adios to those few individuals within earshot, I took off. Head down and focused on the path in front of me to avoid stepping on any resting vipers, I was oblivious to the forest around me as I powered through it.

Sliding down a stream bank perhaps an hour later, I overcame a group of other students just finishing their lunch. After exchanging cursory greetings and asking for any news from up or down our loose convoy, I left them behind. Only minutes later, I heard a sound I typically describe as comparable to a bulldozer clearing a path through the jungle.

Trees in the most areas of the United States (and other temperate areas) have complex and deep root systems. These roots allow the tree to probe the dark recesses of the subterranean world to search for water and nutrients. In tropical soils however, most of the good stuff is concentrated near the surface; as a result, trees in these areas have relatively shallow root systems. These shallow roots may be efficient at gathering nutrients, but they don’t allow the tree much stability. As you might expect, these tropical trees are more likely to simply fall over due to the stress of their own weight. During my two months in Costa Rica, I heard five trees fall over, how many times have you heard that happen while taking a stroll through the forest in the States?

In any case, you’ve probably figured out that’s what I heard shortly after leaving the group behind. A massive tree had freed itself from the canopy, ripped through the neighboring trees and branches, and landed on the ground with a shuddering thud. It sounded as if it could’ve happened on the path. I paused when I heard screams from those behind me, but when I realized they were shouts of exhilaration rather than pain and terror, I set off once again.

Although focused on the ground in front of me, it was hard to ignore the numerous spider monkeys traveling through the canopy above. After penetrating the interior of Corcovado, it was unusual to pass thirty minutes without encountering another troop. Spider monkeys are rare globally, threatened by hunting and habitat loss, but they can be abundant in certain regions, as they are in Corcovado. Likely, their abundance, and the abundance of so many animals here, is related to the history of the forest.

Much of the region was logged in the mid 20th century. When a forest is logged there are plenty of immediate effects, obviously many trees are removed, but the long-term future of the area will be impacted as well. Plants and trees that become established after disturbance of this type are often those species that are fast growing or tolerant of sunny conditions, not necessarily the same species that were there before. In general, they are known as pioneer species, because they are the first to colonize an area after disturbance. Also, species that aren’t marketable for lumber are simply left behind, leaving these undesirable species to make up a disproportionate amount of the remaining individuals.

In any case, these factors have lead to a preponderance of fig trees in Corcovado. Fig trees are thought to be a keystone species in tropical forests, meaning they play a pivotal role in the ecosystem. Many animals rely on fig trees for food; as different trees produce fruits at different times, they represent a reliable source of food throughout the year. And when animals have plenty of food, they tend to produce more young. This is good news for fig eaters like spider monkeys, tapirs, and peccaries. And it’s even better news for the large predators that eat them, like jaguars and puma.

There’s an incredible abundance of animals in Corcovado, but some have speculated that we shouldn’t get used to it. As the forest matures, the conditions change drastically. The canopy closes, letting less sunlight to the ground. Moisture levels rise. The species that grew in the area decades ago may not survive today because they’re adapted to drastically different environmental conditions. This could mean that as the fig trees eventually die off, something else may replace them. And less fig trees means less food for the animals that depend on them.

For now though, Corcovado is alive with creatures. As I walked through the jungle I would occasionally see branches shudder and bend under the weight of monkeys as they leisurely made their way through the trees. Other times, the spider monkeys became aggravated at my presence, screaming and throwing sticks to scare me off (it worked). Yet, other troops seemed content to lounge lazily with only a cursory interest in my passing. What would motivate these troops to have such drastically different reactions to me, I don’t know.


Caught up in the moment and my desire to finish the hike, I suddenly realized it had been over an hour since I had seen anyone else on the trail. As far as I was concerned, I was alone in the jungle. As the knowledge washed over me, the forest suddenly seemed darker, more foreboding, more dangerous. An agouti, a large rodent the size of a rabbit, rustled through the underbrush and I wondered if it was escaping some large predator I couldn’t see. Monkeys screamed in the distance, were they warning other troops of a puma on the prowl? Days later, another student confided in me that at one point during the hike, after he had left the others behind, he became convinced there was a jaguar stalking him. Brandishing his shoe in one hand and a plastic bag in the other, he felt compelled to face the invisible and potentially imaginary predator in a tense (and strangely armed) stand-off. This is what the wilderness will do to you. The true wilderness, where the top predators haven’t been hunted to extinction. There’s no compelling reason to believe he wasn’t in fact being watched, this forest is one of the best remaining habitats for large cats remaining in Central America.

Rather than worry myself to death peering behind every tree, and considering my rapidly diminishing water supply, I decided ignorance was bliss and tried to focus on the path. I caught up to one of the leading groups of people at about the same time as a loud clacking noise startled all of us. At first, I thought I was listening to the sound of a branch snapping in the forest, but I soon noticed a large black form in the trail ahead of us. We had stumbled into the midst of a large herd of white-lipped peccaries and they had noticed us before we had seen them. The clacking noise was that of a large male snapping his teeth together, perhaps to warn us of not getting too close, perhaps to alert the rest of the herd of potential danger. Probably both.

White-lipped peccaries are large animals that travel in herds of up to a few hundred individuals. Formidable opponents for any large predator, an indigenous hunter in Brazil once told me that if you’re hunting them, you better make sure that A) there’s a tree to climb nearby and B) you kill one quickly. A herd of these animals will protect each other fiercely, and their tusks can easily cause a mortal wound. When the peccaries sense danger, they will stampede away; the danger to us was that in any confusion, the herd would charge towards us. I nervously and quickly looked for anything to climb and was relieved to see the spooked herd take off in the opposite direction in a thundering crescendo.

With renewed confidence, we set off anew but hadn’t realized there were still a few stragglers that had taken their time when the rest of the herd had fled. I suddenly found myself about 6 meters (about 20 feet) from a large male peccary that was staring right at me. The beast seemed huge, they can get up to 40 kg (about 90 pounds) and its hairs bristled at our interference. Its face was lined with white streaks, and I knew this was an old and powerful animal. I froze as we looked at each other, and I didn’t move until the peccary snorted and ran off.


It was a fitting welcome to Sirena, which we were quickly approaching. After walking in the dark jungle for so long, we suddenly came to an abrupt break in the trees. Before us lay a huge mowed yard (actually the Sirena airstrip) and I blinked my eyes in the sudden sunlight.


The contrast might otherwise have proved temporarily debilitating if not overcome by the jubilation of finally reaching our destination. I had been hiking for just shy of seven hours. There was only one thing on my mind.