West of the Fields

A tropical ecologist reporting from the field. Musings on life and art, botfly extractions, tropical plant identification, beer, parrots, machetes. Etc.

Friday, October 06, 2006

Where there's smoke... and a bucket of dead rats

When I do a vegetation inventory transect, the fieldwork is only the beginning of the process. The rest of the work—pressing the plant specimens and setting them to dry, entering the data, printing herbarium labels, and sorting the specimens when they’re dry—is not quite as fun, though does involve a much lower risk of snake bite, bala stings, etc. The later steps in my inventory work are not without danger, though, as I discovered earlier this week.

The story starts at breakfast. I was sitting outside on Monday morning, eating my rice and beans, papaya juice, and coffee. I waved to Macho and Don Santos, two of the La Selva staff, as they maneuvered heavily loaded cargo bikes up the path by the comedor. On closer inspection, the cargo turned out to be fire extinguishers.

“A dónde van los extintores?” I asked them. Where are the fire extinguishers going?

“Los llevamos al taller para revisión,” they replied. We’re taking them to the workshop for inspection.

Well, you can probably guess what’s coming up next. At 3 pm, a few minutes after I finished pressing the last of my samples, I met with Orlando to go over the remaining unknowns from my transect. Orlando is the station naturalist, with a truly phenomenal memory for plants. Although he has no formal education past high school, he knows the flora of this region better than anyone else. He started working at the station as a day laborer when he was in his teens. Over the years he’s risen through the ranks to become one of the best botanists in Costa Rica.

I picked up a branch from my rapidly shrinking pile of unknowns. “Elaeoluma glabrescens?” It was a species he had taught me to recognize a few weeks ago—white latex, fat brownish petioles, glossy leaves—but I wanted to be sure.

“Correcto.Y ¿qúe mas tiene?” Orlando speaks perfect English, but he humors me by speaking Spanish. He knows I’m always trying to expand my botanical Spanish vocabulary.

Just then, we heard shouts from the building across the walkway. Someone came running into Orlando’s office. “La secadora está quemando! Vengan!” The plant dryer’s burning.

We ran to the room where the dryers are—tall asbestos-sided cabinets with electrical heating elements that blow hot air over the specimens. A giant plume of gray smoke hung over the building. I reached the back patio of the building in time to see Marcos run out with a stack of burning paper and cardboard. He threw it on the ground, where I helped various people stomp out the flames. Fortunately Marcos was unhurt, only slightly singed. And very fortunately, with the extinguishers all in the taller for inspection (on the far side of the river, a good 400 meters away), nothing else had caught on fire yet. When the worst of the flames were gone, I took a look at the material scattered around us: singed leaves, half-burned scraps of newspaper. With my name and collection numbers on the upper right-hand edge. I felt sick, seeing a day’s work scattered and smoking on the ground.

In order to make an herbarium specimen, you carefully press a section of a plant in newspaper, folding the sample to show all the salient features that might be useful for identification: both sides of the leaves, the delicate ends of twigs, etc. (Fruit and flowers, if you’re lucky, but with transect vouchers you take what you can get.) Mark the newspaper with your name and your collection number, a uniqe identifier for each specimen you collect. Between each sheet of newspaper, you place some blotter paper or cardboard so that the twigs of one specimen don’t leave marks or wrinkles on the leaves of the next. Every five or six sheets of cardboard, you add a layer of corrugated aluminum. (These aluminum corrugates, I discovered on a field course some years back, make a great substitute for washboards if you want to play old-time music.) When you have a stack about a meter high, you put wooden frames on either end and pull it tight with straps to keep the specimens flat as they dry.

After we had made sure that the fire was out and nothing else in the dryer had caught, I reassembled as much as I could of the stack of specimens. Most of the plants were burned beyond recognition, but a cursory examination showed that it wasn’t as bad as I had feared. Of the three presses I had filled that day, only one had burned. Marisol carefully gathered the remains of the branches we had discarded, while I sorted through the burned paper and cardboard looking for salvageable pieces.

At La Selva, we have plenty of metal corrugates and wooden press-ends, but we’re rather limited by newspaper and cardboard. Fortunately I have the address of a recycling center in San Pedro where newspaper is 50 colones (about 10 cents) a kilo, and I’d recently picked up a stockpile. But cardboard… I was only able to recover four or five pieces from the burned stack. In order to reconstruct the specimens I’d lost that day, I would need at least eighty.

I must have looked pretty glum and resigned as I headed over to the cardboard recycling pile behind the Taller. Erin and Isabel, two recently arrived long-term researchers, met me on the bridge.

“What’s up?” Erin asked. “You don’t look so hot.”

When I explained the situation, they came to the rescue. They helped me lug all the useable cardboard scraps back to the lab, and slice them into proper-sized pieces with box cutters. A job that would have taken me well into the night was finished before dinner, and I was able to reconstruct all my lost specimens—all but one—by 9:30 at night. The one I lost was a common and easily identified species, Smilax domingensis. Orlando examined the dryer, and found that one of the shelves has been mis-positioned after a routine cleaning, placing it too close to the heating elements. There are new signs on the dryers now, showing clearly where the shelves are supposed to go. I guess the adage is true, all’s well that ends well. But I shudder to think what might have happened if nobody had spotted the smoke.

The bucket of dead rats really had nothing to do with the immolation of my specimens. It was just the other noteworthy thing to happen to me this week. Dennis, a herpetologist and the current record-holder for longest consecutive stay at La Selva (among current researchers), is radio-tracking fer-de-lances. These giant pit vipers—a meter and a half, or sometimes even bigger—are one of the things in the forest that I go out of my way to avoid, but Dennis has been capturing them, surgically implanting radios, and tracking them, for more than two years straight. He has about ten snakes now in the field with little transmitters sutured to their ribcages. Every day, alternating day and night, he goes out with a giant antenna and a little beeping receiver, and he records their whereabouts. Even by day it’s not for the faint of heart—he works in swamps, treefall gaps, and hideously tangled spots. The mosquitoes are horrendous. And as Dennis’s assistant Vinny discovered the other day when one crawled over his foot, not all the fer-de-lances have radios.

In the past few months, Dennis has been conducting a feeding experiment with half his tagged snakes, in order to see how food supply affects their home ranges. As it turns out, the fed snakes have much smaller home ranges. I guess it makes sense; if there was a Krispy Kreme shop right outside my door I wouldn’t move much either. But it’s not Krsipy Kremes that the snakes prefer. It’s rats.

A few nights ago, Dennis and Vinny invited a few other researchers along for Feeding Night. We gathered on the back porch of the old lab, beside the hammock and the much-mildewed leather rocking chairs in the “rincon de vagos” (lazy people’s corner). As the last straggler came out of the lab building (Erin, pulling on her wet boots with a curse), the rain began.

“Typical,” Dennis said. “We’ve done, what, like eight feedings now? And I swear, seven of those nights it’s been raining.” He shouldered his transmitter and a long, extendable plastic pole, and he slung a bucket in my direction. “Here, you can carry this.”

I looked in the bucket and rather wished I hadn’t. There was a thermos full of hot water—pit vipers, after all, won’t eat cold food—and a bag of slowly defrosting white rats. Mmm, whiskers.

We headed out into the Research Swamp for the nearest snakes. With the moon behind rainclouds, the night had a velvety darkness so thick that the walls of forest outside the narrow beam of my headlamp seemed to be closing in. Rain dripped incessantly off the leaves, the sound blending with the little murmurings of night creatures.

After maybe twenty minutes of crashing around in the underbrush beside the swamp, listening for the transmitter’s faint beep above the sound of the rain, Dennis located the first snake. Her raised head was sticking out, alert, from under a rotting log. It was hard to tell how big she was, except for the glimpses of hefty wrist-sized coils stacked up under the log.

“Good, she’s hunting,” Dennis whispered. “Drop a rat in the water.” (Fortunately this task fell to Vinny and not to me.) “You guys stay over there. Turn off your lights and be quiet. She’ll spook if she hears us, and then she won’t eat.” We complied. Dennis made a few adjustments to the plastic pole, and fished the now-steaming rat out of the water. He tied a slip knot around its tail with the string at the end of the pole. “OK, here we go.”

He turned his headlamp to the place under the log where the snake had been. There was nothing there. In that moment the fitful rain stopped and the moon came out, lurid and brilliant, lighting up the layers of black leaves and the long streaks of water dripping from the canopy. Low branches hung with moss looked skeletal and furtive. In the eery light I strained my eyes for a glimpse of anything that might indicate the whereabouts of the snake: the white patch beneath her chin, or the zigzag pattern of her back. Nothing.

“You got a signal, Vinny?” Dennis asked. I heard the boop-boop-boop of the transmitter, rising in volume. “Ah. Under that palm. Step back, Vinny. Step back.”

Dennis directed us to the far side of the log, where we would have a clear view of the snake and its dinner. Then, carefully balancing the plastic pole on the waist-high rotten log, he extended the pole until the rat dangled right in front of the snake. She came forward slightly, and WHAM! She lunged upward, allowing us a momentary glimpse of the lethal fangs as she sank them, rather superfluously, into the neck of the reheated rat. Some profane exclamation escaped my lips. Even after witnessing Franklin’s anaconda bite, I had forgotten just how quickly snakes can move.

In other herpetological radio-transmitter news, Steven (another resident herpetologist) has come up with a great way to deal with the crocodile issue. On hot days like today, it would be delicious to go floating down the river on inner tubes the way we used to—but with a crocodile frequenting our old swimming beaches, floating activity has come to a halt. Steven’s idea is that we should contact Google and have them send down a team of specialists to capture the crocodile and tag it with a GPS transmitter. It could become a new feature on Google Earth—any time you wanted to know where the crocodile was, you’d just have to go on line and check. They could also paint the Google logo on its side, opening a brand new dimension of corporate sponsorship. I’m sure Google Crocodile, as we would call him, has the potential to become a great tourist attraction as well.


At 12:52 AM, Blogger LadyGrey said...

I sent the relevant part of your story to a friend at Google, though I don't think she's in a position of sufficient power to create Google Crocodile.


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