Engineer's Notebook: The Wilderness Chorus

Editor's note: NPR engineer Flawn Williams kept a diary of his journey to eastern Ecuador to capture the sounds of the Amazon — follow his day-to-day journal, and hear his own report on his quest to record the spectacular bellows of the howler monkey:

Arrival

We tied up at the rickety dock at the Tiputini Biodiversity Research Station, an outpost in the Amazonian rainforest of eastern Ecuador, after a two-day trip. It had started with three airplane rides (DC-Houston-Quito-Coca), then climbing into a big steel canoe for a speeding two-hour ride down the gigantic Rio Napo, a tributary of the Amazon which even this far upstream is wider than the Mississippi is at Memphis, Tenn. From Pompeya, an open-sided bus took us on a jolting dusty two-hour ride down an oil company pipeline road, with various delays along the way. The final two hours were in another steel canoe, motoring down the narrow, deep, silty, sinuous flow of the more intimate Rio Tiputini.

That final boat ride had been an adventure in itself. One of the outboard motors kept choking as we started downriver, and the pilot was focused on restarting it, rearranging the plastic hoses that led from fuel cans to the motors. We drifted close to one bank then the other, as the river carried us through hairpin turns. Fallen trees bobbed against the strong current like river giants struggling to get upstream. Birds of many sizes and voices flashed across the river canyon, and we sighted tapirs, turtles, and pink river porpoises along the way. And trees! This is a rainforest, and both rain and forest were around us in profusion. Astonishing trees of sizes grand and small loomed along the riverbanks, shifting slowly into silhouettes in the fading afternoon light.

Astride the equator, the sun always sets at about 6pm, and we arrived at camp after dark. We climbed many wooden steps up to the dining pavilion of the camp for a welcoming and briefing, grabbed our gear, and were led to our cabins down rain-soaked pathways punctuated with log sections for better footing. We didn't know it at the time, but it was a good thing the buildings were built on high ground: the river would rise 15 feet during our seven-day stay. And this is heading into the dry season!

Tiputini is a shrine to diversity. In the average acre here, there are more species of trees than there are numbers of trees in an acre of American temperate forest. Animals, reptiles, insects all follow suit. Kelly Swing, a professor leading a student tour at the station, told us that after 15 years of observing here, he still can't go for 15 minutes of walking without seeing something he's never seen before. There are still things here that have probably never been seen by humans, at least not seen in the sense of being named and categorized.

For us, even that first wet evening trail walk to our cabins held wonders. Frogs that would fit on a dime, shone like a glossy nature magazine cover. A katydid the size of an outstretched hand paraded with arrogance to match its size. Beetles flew overhead with twin green lights set into their shoulders, glowing so bright and constant they looked electrically powered, and with equally bright orange lights on their undersides. Tarantulas of intimidating proportions sauntered about on their evening rounds. And moths by the hundreds, seemingly no two alike, thrummed in the air.

Cabins were duplexes, each room able to sleep five, but I got one to myself: one bed to sleep on, and four on which to spread out my sound recording equipment. Screens kept out most bugs, and the resident spiders took care of the rest. The bathroom included running water (cool only), gathered from rainfall and the river, then treated until it was pronounced by the management (and later proven by my innards) to be safe for drinking. A good redoubt for a few days in wildness.

Raindrops dripped from leaf to leaf in the woods of Tiputini long after the rain stopped falling above the forest that evening.

Day 2: First Light

It being the equator and all, sunup was at about 6 a.m. But daybreak approaches before that, and with the first light comes the dawn chorus of birds, monkeys and myriad other creatures happy to greet the day.

In the small courtyard framed by our cabins stood a single tree, and in that tree the morning light ignited the voices of a dozen or more pairs of oropendola, a spectacular species of bird about crow size, basically black but with brilliant yellow tail feathers that flashed into sight only when the birds took flight. Their voices ranged from sounds like gigantic boinging raindrops (now where might they have gotten that inspiration?) for the adults, to the raucous plaints of nestlings awaiting food. The nests themselves were a sight to see in the early glow: two-foot-long teardrop shapes woven of mosses and twigs, suspended from the branches of the tree.

After breakfast at 6:30 (good basic foods, pancakes and fruit, always with peanut butter and sugary drinks on the side, served in the open air pavilion), we headed out for a first exploratory walk with Rex Cocroft, the insect scientist we had accompanied to Tiputini. He specializes in studying treehoppers, small but prolific insects that suck sap from stems and manage to have an amazingly complex and vocal social life in the process. Rex's studies have shed new light on their lives, including ways that they communicate by sending vibrations along the stems of the plant they inhabit. He's done field research in the U.S. and many other countries, but this was his first trip to Ecuador.

We weren't more than five steps from our front porch when he spotted his first community of hoppers.

Tiputini is a research station, accommodating a small group of long-term resident researchers, some short-term visiting scientists like Cocroft, and occasional birders and other non-researchers to help pay the bills. We were being accompanied on this first hike by a staff guide, Henryk, who was there to get us acclimated to the trails and serve as the local expert. But Henryk came with no particular knowledge of treehoppers. He was well versed in the several species of monkeys, large cats like jaguar and puma, and reptiles like anacondas and caimans, that were the better-known lures of this reserve.

Within minutes of being shown that first group of treehoppers by Rex, though, Henryk was spotting them like a pro. We racked up species after species, seeing mating adults, females minding broods of immatures, nymphs just hanging out, various social arrangements of hoppers being tended by ants in symbiotic unions. We made notes of many promising sites to come back to with recording gear to listen to these critters in the field, and snipped a few branches into big Ziploc bags, kept fresh with florist's water tubes, to carry back for study in Rex's makeshift lab on the porch of his cabin.

There are lab facilities for researchers to work in while at Tiputini. But for Rex, as well as for us, these buildings were a mixed blessing. They were air conditioned for several hours a day using generator power. But Rex's work listening to the minute sounds of the treehoppers requires near-complete stillness. And the noise of the powered gear, and footfalls of other people on the boardwalks that connected many of the buildings around camp, plus the creaking of corrugated metal roofs expanding in the sun and contracting in the rain, all compromised the calm of the wild Rex had been expecting. So he set up shop on his cabin porch, as far from the rest of camp as possible. Later he would take his lab into the woods, using a screen tent and other gear that Alex and Carolyn had brought along for our use.

For us, too, the engines of civilization created problems. We couldn't get clean recordings of voices or forest sounds within half a mile of camp when the generator was running...or if the boombox in the kitchen was blaring out music or a ball game. So we planned our daily tasks to avoid, as well as take advantage of, the trappings of power afforded by the generator.

The daylight hours brought views of new flora and fauna. A mantis, about the size we're used to seeing, but with a heart-shaped leafy mantle atop her shoulders and a long skinny leaf form above her body, perfect camouflage for the plant she sat on. Scarab beetles, iridescent in the sun and shiny like a well-polished opal. Butterflies of many hues and sizes careened through the air, including the huge blue morphos, which were surprisingly among the most common of the butterflies near camp. The brightness of the flash from each wing-beat of a morpho is not to be believed, even though I've admired the static blue glow of the specimen we've had at home for years.

There were also cautionary tales told to us, of things to be alert for, things to avoid. Snakes hanging from trees, snakes on the ground. Two-inch-long ants with fierce bites that like to hang out on the handrails of bridges across the little creeks along the forest trails. Spiders from tiny to gross, with that seeming inverse relationship between size and danger. Peccaries with malice aforethought. A 20-foot anaconda in the lake at the west end of the complex. But we saw little of these things, while we reveled at the wonders in the woods. A frog the size of a peanut, black and bedecked with markings of royal gold.

In the afternoon it rained, a shower coming up quickly and then tapering to drips within minutes. Sometimes the rain is preceded by a tiny burst of cool air. Just when you're relishing the cool air comes the realization that heavy rain is hot on its heels.

After the drips had ceased Rex and I spent some time wandering around camp, testing our recording gear together, finding ways to increase the audibility of the hoppers and decrease electrical noise. Again, the diversity of what we found within just a short stroll of our cabins was awe-inspiring. Tiputini is reputed among scientists to harbor the greatest diversity of any spot on earth. I'm not a trained recognizer, more of a naïf in the woods, but this forest is a grand place for innocent wonder.

At dinner we talked to several of the resident primate researchers. Monkeys hereabouts include howlers, spiders, squirrels, sakis, and titis. Among howlers, there's usually a wide territorial spacing of groups, but the conditions around Tiputini support four groups within audible range of one another. The howlers use vocalizations to tell other groups to keep their distance. Better to say "I'm stronger than you" with a bellowing squall than to have to fight hand-to-hand for your territory.

A couple of researchers offered to take us out to record their subjects the next morning. We said yes.

Day 3: Sudden Silence

Abigail Derby has been tracking howler monkeys at Tiputini, in the adjacent Yasuni National Park across the river and in other places for more than a year as part of her doctoral studies. She has outlined a quick recording opportunity for Alex and me — we'll meet at the research office and listen from the porch around 5:30 a.m. If the nearest howler group is calling today, they'll start about then, at dawn's early light, and howl for fifteen to thirty minutes. If we hear them start, we can hotfoot it into the forest to locate them, and record them when we get there. Sounds like a plan.

At 5:30, the dominant male of the nearest group of howlers is already howling. From hundreds of yards away, the sound is intimidation personified. It's not the howl of a wolf or coyote. It's more like the howl of a hurricane clearing its throat, squalling and brawling through the morning air, reverberating through the forest to reach our ears. Abigail says howlers have an enlarged and hollow hyoid bone, which allows the resonation of their low-pitched sounds to travel long distances.

We scramble out of camp and along the Matapalo Trail for several minutes, then veer off the trail after localizing the source of the terrifying noise.

The rest of the tale is on the tape. Crackling through underbrush, trying to make more time and less noise. Stopping for a moment to reorient, then pressing on. Finally arriving at the base of the tree where the howler group has spent the night. Stifling our panting breath to avoid messing up the monkey sounds being picked up by the highly amplified stereo microphone array I'm carrying on a stick.

Eight seconds later, the howling stops.

The dominant male is confident that he's warned off all potential interlopers this morning. He's done vocalizing. We're left recording just the quiet details of forest ambience. Soon, the birds' dawn chorus will rise from these woods.

Even the distant sound of a dominant howler male from another group about a kilometer away, across the river, isn't enough to get another vocal rise out of our local alpha male.

Abigail looks at her watch. It took us 13 minutes to reach this spot.

There's also a small colony of squirrel monkeys waking up in a treetop right above us, and Abigail predicts that when they see us they'll start vocalizing.

They don't.

She says this howler group often overnights in one of several trees in this general vicinity. I resolve to come back another morning, earlier than 5:30, and hope the howlers are feeling vocal that day.

Abigail Derby has been studying primates at Tiputini, comparing them to other groups in the park across the river. There is human hunting of primates at the other site, but not here. But the oil exploration infrastructure that has made this area more accessible for researchers also portends a danger for Tiputini. The research station's land holding is midway through a 25 year concession grant from the Ecuadorian government, and while there's hope that the concession can be renewed into the future, incursive roads and other oil development nearby could be disruptive to this 65 hectares of somewhat corrupted Eden.

Scientists here have been encouraging the oil companies not to build roads, but instead to use techniques more like offshore drilling platforms to extract and pipe the oil out. These methods are more expensive, but far less damaging to the health of the rainforest.

Helicopters from the oil camp downriver occasionally fly low over the forests near the station, sometimes as often as once a day. The monkeys, according to Abigail's observations, react as though to a very large aerial predator.

After breakfast, Alex and I make a trip into another section of the forest with researcher Courtney Sendall, looking for the troupe of saki monkeys she studies. She's equipped with a radio tracking system, and some of the monkeys wear radio collars, but even with such aids we don't find them for a while, and when we do get a fix on some they're hundreds of meters away...Courtney reckons they're back at camp.

We do hear some titi monkeys in the distance, and head off to hear them, but they decide to get quiet too.

What we do hear is hammering. There is construction going on at Tiputini, more new dormitory space to replace some of the original structures that are now more than ten years old. Hammers and generators and occasional power tools will pockmark some of our soundscapes. It's part of the story, though not part of the magic. And at just past 8:30 a.m, we're completely drenched in sweat that doesn't evaporate. Temp around 80, humidity around 100.

Later that morning, I head farther out with a surround sound recording rig to tape some more pristine environments in the forest. Along the Chorango trail I find no big charismatic megafauna, but a pleasant daytime scene of birds and insects. Along the Harpy Eagle trail there's a small bridge, where a stream winds through a rocky outcrop. The water trickling through there makes a lovely sound that I capture from two perspectives. (A harpy eagle is a large bird, which does occasionally prey on monkeys in the canopy, so those howlers do know something of predation from the air.)

In the afternoon we head into the forest with Rex to photograph and record a colony of treehoppers. Tree-falls are treehoppers' friends... the fallen behemoth opens a gap in the canopy so light can hit the forest floor, stimulating growth of new plants that the hoppers thrive on. We listen to this bunch for a while, and take their pictures with Alex's fancy camera rig. But even with the little Nikon and Canon quickie cameras that Rex and I have, set to super macro mode, the treehoppers can be pretty photogenic.

One thing we learn from Rex in this session is that while we can't hear the treehoppers' plant-borne communications, they may be able to hear ours. The plants act as a transducer for noises traveling through the air, and so our voices sound almost as loud as the treehoppers when picked up by Rex's contact sensors on the stems.

Day 4: Who Has Heard The Rain?

I'm spending Halloween here in the land of outlandish animals. I had hoped to revisit the horrific sounds of the howler monkeys this morning, but it's raining heavily. So instead I make lemonade by concentrating on getting a good recording of various aspects of the rain. It's one of the hardest sounds to capture evocatively, but I have plenty of opportunities to try this morning before and after breakfast.

Rex wants to get a reference recording of what raindrops hitting the plants sound like through his contact sensors. So we suit up with umbrellas and gear and head out to our favorite tree-fall area. The treehoppers are silent today, but the raindrops hitting their plant make an infernal racket — somewhat like the sound of raindrops hitting our umbrellas, but amplified hugely.

By afternoon the skies have stopped dumping water on us, so I take a solo hike along the Lago trail, a riverside ramble of over two kilometers that leads to a 130-foot-high observation tower overlooking a lagoon. It's more of a personal pleasure outing to get farther from camp, but just in case I take along stereo mikes. And sure enough, I find some lovely soundscapes to record along the way.

I also find a camera trap, a place along the trail where cameras are set up to catch animals as they wander past. The researchers are documenting far more deer, jaguars, and other big ground critters with these camera traps than by direct observation. But there are instructions posted nearby to show hikers how to avoid setting off the camera trap. It goes to show that either the jaguars can't read or they don't care about the automated paparazzi.

The tower, when I get to it, is a somewhat rickety set of wooden steps framed around a giant old tree, going up and up above the rest of the canopy. After a few days down in the forest, emerging from the canopy to have a 360-degree view to far horizons is a thrill. Almost enough to make me forget that active termite trail I saw on the wooden stair treads about halfway up the tower...

It's also a great place to see dozens of varieties of birds, including scarlet macaws, gliding from treetop to treetop. I can't see all of the lagoon...in fact, as the forest has grown around the lake, I can't see much open water at all from the tower. So I get no glimpse of the anaconda or giant caiman reputed to be dwelling therein.

Back at camp, Alex and Carolyn report that a large tarantula has been found in, and removed from, Rex's cabin. Next they found a somewhat smaller one behind the curtains in their own room, and it too was escorted from the premises on a plank. I'm probably the only one in the group who would be fine with having a tarantula hanging around my room, but a careful check of my cabin shows only one, and it's on the outside eaves.

Day 5: The Early Bird... Gets The Spider

No rain can be heard this early morning when I rise at about 4 a.m. By 4:30 I'm treading softly into the dark forest along the Matapalo trail, navigating by headlamp and handheld flashlight, carrying a lightweight recording rig and a tripod. For quiet situations that need lots of amplification, being able to leave the mikes on a tripod and walk several feet away results in far fewer bumps and breaths on tape than if I'm trying to handhold the mikes for the whole recording.

At my first stop along the trail I hear some interesting night birds, crickets and cicadas. But there is also a recurring low-pitched sound, patterned like a bird call but in a register lower than the bottom of my baritone voice. It's more melodic than a snore, but sounds like something that could be sleeping. I move closer to the mysterious sound and record for a while, then head farther into the forest for my appointment with the howlers.

I arrive at the 660-meter marker along the Matapalo trail, my landmark from a few mornings ago. I set up the gear, and start recording at 5:33 a.m.

Less than two minutes later, my quarry — the dominant male howler monkey — starts in to howling. He and his group are less than 100 meters away from me, and a hundred feet up a tree. I reposition to get somewhat closer and re-aim the mike in his direction, then continue taping his recitative. This time instead of eight seconds I get nearly eight minutes, without the sound of me clattering in the undergrowth. My karma account must have been recharged.

Later that morning I also get some saki monkey recordings, so it's a good day for primates — for some of us, at least. One student group that is visiting the camp comes back from a hike with reports of seeing four different species of monkeys; the other half of their group, walking the same loop trail in the opposite direction, saw none.

We want to do a more extended interview with Rex about his work, and it's become obvious that the taping can't be done cleanly in camp during the day without lots of non-rainforest sounds impinging on our ears. So at mid morning our whole group sets off along the Lago trail, checking out clusters of treehoppers along the way. The river has risen a few more feet since I walked the same trail the day before.

Alex, walking in the lead a kilometer or so down the trail, comes within inches of putting his face into a cross-trail web occupied by a spider nearly the size of his hand. It's got a dark back, a yellow speckled belly, and enormous jaws. Look up, look down, look straight ahead. Be. Here. Now. This is the perfect place to practice that mantra: be alert to the here and now, both for the danger it may hold, and for the wonder it certainly will show you.

After lunch we interview Kelly Swing, an ecology professor who was instrumental in establishing the Tiputini Station. He arrived Monday with 15 seniors from Boston University who are doing a semester abroad in Ecuador, with a month at Tiputini as part of the program. He's an easygoing eastern North Carolinian with an abiding love and deep knowledge about this rainforest.

The rest of the day is spent cataloguing tapes and transcribing interviews. Carolyn Jensen, our producer, has already been doing a lot of this — as I finished each digital audio tape, I have cloned a copy for her to listen to. Because it's hard to get time for Alex to concentrate on writing pieces for this project once he's back in the daily deadline world of his regular hosting job, she wants him to structure and write the stories, and perhaps even record his voice tracks for them, while we're here at Tiputini. So apart from a few sessions talking with Rex at his porch lab, listening to treehoppers culled from the forest, our sound gathering is done. I stay pretty close to camp, help log and organize the sounds, and am on call for assisting Alex and Carolyn as needed.

Day 6: Making Sense Of It All

The scenes begin to feel familiar as the sun rises. But each day brings a different mix of rain and sun, a different array of new insects and other life outside my door (and a few new ones inside too!). I'm already reliving some moments by sitting on my porch and listening to the tapes, while in the rainforest life continues to press on.

This is also a chance for a few brief forays out with the camera. Often when I go out on such trips I come home sans pictures, because I've always got mikes in hand instead. But this time I can take some pictures too. And my camera has come in handy for grabbing quick images along the way, too, when setting up Alex's pro camera would be impractical.

I'm also, sad to say, starting to pack and prep for leaving Tiputini. It's a sorrowful moment, because I'm just starting to feel at ease with the rhythm of the place.

Day 7: A Stranger Drops In

Much of this day is also spent under production deadline, logging and listening to sounds on tape, and preparing for the possibility that the pieces may be written and ready for voicing by day's end. Alex is hunkered down on his porch with his laptop computer (and with my iBook when the battery in his dies), culling the tapes for the best bits of wisdom and crafting his signature narratives to flesh out the story.

I continue tearing down the recording rigs and repacking. Much of the gear I'm using will travel back to Los Angeles with Alex and Carolyn, to be handed off to another engineer for immediate service on a Radio Expeditions trip to the Mekong River. So I'm starting to think outside our happy rain forest home, and prepare for the trip out, while staying ready to record Alex's voice tracks if we get to that point.

Every change in the weather is carefully studied, wondering about the prospect that when Alex is ready to record, rain and thunder might make that impossible to do. A quick shower comes through, but mostly the day is calm and conducive.

By day's end, we have rough drafts of two eight-minute radio stories, but are not ready to record the final versions. It's been a good exercise in deadline pressure, pushing the crafting of the pieces much farther along than we usually do in the field, so that'll save a lot of effort back at home in postproduction. But it has taken away some chances to spend time recording these past two days.

Meanwhile, Rex and his associate Lin from Taiwan are making good strides in getting better recordings of the treehoppers. And they'll be staying on a few days longer than us, so there will be more material coming back with them that we'll be able to choose from for the most evocative little insect sounds.

At the dining hall that night, as we finish our "last supper", the Boston University students in Kelly's group have acclimated to camp well and are eating and carrying on lively conversations. Then suddenly there's a shrieking commotion.

A large tarantula has dropped out of the rafters above one of the tables, and landed squarely on the head of Nina, a young Chinese-American student. She freezes and hunkers down as everybody around her screams and mills about. Finally someone gets an implement and manages to brush the arachnid off her head and encourage it across the floor to exit the pavilion.

Nina is shaken, but recovers quickly. Others in her group may take longer: one young woman, who has reportedly already been sleeping inside a mesh tent set up within her cabin, sits meekly at the end of the table, finishing her dinner, her rain jacket hood snugged tightly around her face.

Nina had sat with us at a meal earlier in the week, and had mentioned she was taking Lariam antimalarial medication. We wondered at the time whether she might encounter some of the hallucinatory side effects of that drug. After this incident, we wonder what her dreams will be like tonight. And as for our own dreams, we're glad we're taking Malarone instead.

Back at the cabin, I finish the packing after sorting out unused snacks and batteries to leave for the resident researchers to enjoy. And then I lie down to commune with the night sounds outside my cabin for the last time.

Day 8: From The Outdoors To The Outside

The boat is ready for us as soon as we finish breakfast, and our luggage is loaded. There are far fewer steps down to the boat, as the river has risen about 15 feet since we arrived a week ago. We wave farewell to Rex and Lin and Kelly, and head off upstream.

On the way in to Tiputini a week ago I had spent much of my time on the boat either recording the sounds of water and motors and excited birders, or huddling under the canopy out of the rain. This morning there's no further recording to do, though I have mikes nearby if needed. And the weather is beautiful. So I sit yoga-style on the raised prow of the steel canoe, take an occasional short movie with my camera, and watch the riverbank forest go by.

It's a beautifully meditative couple of hours. We pass perhaps 50 miles of riverbanks, with only one structure, few "curb cuts" and no people or other boats seen. Only the intense green of the trees, the silty brown of the waters, and the flashes of color from occasional flowers, birds, and blue morpho butterflies.

When we reach the bridge where the road to Pompeya crosses the Rio Tiputini, we prepare to disembark. There's an indigenous Wuarani family tending their boat at the landing site and washing things in the river. One young boy is carrying a big inflated innertube. His sister, hardly more than 6 or 7, is carrying a hefty machete down the slope. And the father is wearing a T-shirt emblazoned with the rampant lion emblem and logo of Chiemsee, the Bavarian lake resort near Salzburg, Austria. Salzburg will be my next, and very different, port of call. From morphos to Mozart, all in a season's work for NPR.

After two hours of dusty jostling in the open air bus back to Pompeya, and a nap on the bus bench seats while waiting for our next boat to arrive, we motor back up the Rio Napo on the final water leg of the trip. After the intimate charm of the Rio Tiputini, the Napo feels huge and exposed. It appears to have risen no more than a foot in the week since we last saw it.

Every few minutes, another boatload of eco-tourists zooms by, seeming more thrilled by the speed of their boat than by what they can see along the shores. These riverbanks are heavily altered by houses, industrial sites, and forest clear-cuts for banana palms and cornfields.

Arriving back in Coca, we check our bags at the airport, then walk next door to pass a couple of hours in a little restaurant. A TV is blaring inane programming at top volume. The restaurant is out of sandwiches and soup. We settle for ice cream bars and French fries. It's not a convincing welcome back to civilization.

A short flight later on Icaro Airlines, we have left the rainforest behind. The wisdom of naming an airline after Icarus, who fell after flying too close to the sun, is lost on us. We fly between the snow-capped volcanic peaks of the Andes before dropping into an alpine valley for a safe landing in Quito. Above 9,000 feet, the air is thinner and cooler, even at the equator. There are far fewer bugs, and fewer oxygen molecules too. By next morning we are out of Ecuador entirely, flying back to Houston and home.