Our patience was wearing thin. It had rained steadily for three days straight and we had less than a month to get our experiment done. The was no time to waste; we had to go in.
I learned quickly that nobody in La Selva took any special precautions against the rain, no umbrella, no raincoat, nothing. The only rule that was scrupulously followed was pure common-sense: never venture into the forest without your headlamp. As we prepared to set out that evening, Hilda made a point of packing several extra batteries.
“There’s nothing you can do if something goes wrong with your headlamp,” she said earnestly. “You’re helpless, Sam, you can’t do anything. You really don’t want to be stuck in the forest at night without light, you’ll never find your way out.”
I nodded fervently. Even for me, a girl who thought a day climbing trees in search of scorpions time well-spent, being trapped in the forest without a lamp after nightfall was the stuff of nightmares. The suffocating darkness and resultant panic would ensure I was either bitten by a snake or squished under a falling branch, even if I didn’t wander off the path into the swamp.
Once we actually caught a few bats, we had to take them to our flight cage, and we had to do it without distressing or hurting the animal. The standard practice was to put the bats into small drawstring bags made of soft cloth, so the bats could hang comfortably in there, and either hold them if you walked back, or hang them on the handle-bars of a bicycle if you were biking. Now we had two bicycles, Hilda’s new bike and one I’d rented from the reception, and we got them out.
We rode slowly, blinking away the rain and trying to stop the bikes sliding into the mud. It did not help that there were now a thousand frogs swarming over the path, eyes gleaming like rubies in the blurry twilight. They all seemed infected with a Darwin-proof desire to throw themselves under our wheels, and more than once I had to skid to a halt to let one of these suicidally stupid animals hop out of the way. By the time we got to the hut I was strung-out and tense from this amphibian obstacle-course, but Hilda was unfazed.
“It’s raining a bit less now, maybe it’ll stop soon!” she chirped.
I wasn’t sure about that, but I didn’t think it mattered now. The ground was just one big mud puddle, and our net, our precious untangled net that we had set up three days ago, was soaked through.
“Oh God, no!” Hilda squelched through the mud and gave the net a flick. “We should have put this under the roof – I just didn’t think of it, and now look at it.”
“Will it still catch bats though?” I asked anxiously.
“Oh yeah, sure, but now it’s all wet and drippy and it’ll stick.” She poked it again fretfully. “Here, help me get it under the roof.”
We yanked the poles out the soft ground and shifted the net a few inches backwards so it was now completely protected by the rusty metal roof, and then hung up our nectar-filled feeder for bait.
“Now we have to untie the net and open it up,” said Hilda. She calmly wiped her wet face, swatted away a few mosquitoes and got to work. The idea was to simply the pull off the ties and untwist the net so that the folds came apart and the net could be spread out to form what was essentially a wall-sized spider web. Yet, no matter how much we twisted and untwisted, it was no good. The net simply hung there, a sodden mess of a tightly furled rag.
“What’s wrong with it?” I cried.
I was starting to lose my head. Far from abating, the rain was coming down with a vengeance. The mosquitoes were having a field day, somehow weaving through the falling droplets to deliver knife-pricks of fury to my face and neck. It did not help matters that my headlamp, just above my eyes, was now a screaming beacon to every insect in a half-kilometer radius. Flies, beetles, moths, and countless little bugs I couldn’t ever name were beginning to swarm around us, getting in my eyes and throwing themselves into my mouth. And here was the dripping net, firmly knotted as ever with the threads sticking together as though the water was so much glue. I might well have crossed the line into hysteria if Hilda hadn’t been so calm. We struggled away until we had the folds separated at the ends of the net, then found to our disgust that this had created a bigger knot than ever at the center. For a while we simply waded back and forth through the mud, spitting out insects and blinking away the rain. Ten minutes in, I got myself into a particularly sticky patch of muck and glanced down at my boots.
“Aah! Aah! Aah! There’s ants in my – aaaaaah!” I hopped up and down and slapped at my legs hysterically. A line of leaf-cutter ants were making their way across the ground and at least twenty of them had crawled up my boots and were about to get inside my socks. I swung my headlamp over the ground and picked out a veritable army of leaf-cutters swarming out of a nest behind the old shack.
“It’s okay, it’s just leaf-cutter ants,” said Hilda soothingly. “Did they bite you?”
“No… no… no, oh God, oh God! But they nearly got me.” My words came out in frantic gasps.
“You just count your blessings.” Hilda pointed at the hut. “We used to have a bullet ant nest over there; thank God that’s gone.”
I glanced at the hut. I breathed a silent, fervent prayer. I usually prided myself on my love of all creatures great and small, but I was unapologetically terrified of bullet ants. An entomologist named Justin Schmidt, while studying the toxicity of harvester ant stings, came up with a scale to measure the pain of insect stings. Dr. Schmidt had been stung by dozens of different kinds of insects, and said that the pain caused by the bullet ant was literally off the scale. It was, in his words, a “pure, intense, brilliant pain. Like walking over a flaming charcoal with a 3-inch nail embedded in your heel”. And it could last over twelve hours. There was even a La Selva legend about a scientist who hadn’t inspected his bicycle before mounting it and accidentally sat on a bullet ant. Maybe I was a pansy but I’d take leaf-cutters in my socks over that any day.
I gave my boots one last shake.
“I think I got ‘em all out,” I said, brushing away a jewel beetle from the net. I glanced up at the metal roof and nearly screamed again as my head-lamp caught something black… hairy… sparkling… I peered carefully. A wolf-spider, but oh what a big one! She was nearly the size of my palm and every one of her eight eyes caught and reflected the light of my head-lamp. I shook my head and then grabbed the net again.
“But what are we going to do about this thing? Would the bats even get caught in it with that big knot?”
“Well let’s see if we can open it up…”
It was only two minutes before I realized how stupid my last question had been. I was bent over the center of the net, holding it as Hilda threw the folds back and forth to separate them, when something softly whirred past my cheek. I looked up and turned around to see the unmistakable flutter of bat wings disappear into the darkness.
“Was that a -”
“Hey, the bats are here.”
“Holy God, no!”
Even as we struggled with the net, more and more bats began to show up, gliding by and targeting the feeder so precisely they missed us by inches. I saw one bat after another at the feeder, sipping at the sugar, utterly untroubled by the two frantic humans and their silly wet mist-net.
“They’ll go away before we open the net!”
“Quick, just get this bit open!”
I was just beginning to wonder if we ought to call it a night and come back with a better net when I realized my end of the net was twanging back and forth.
There was a bat in it, a very angry bat, furiously trying to free himself.
“Bat! Hilda! Quick, Hilda we got a bat! We got a bat! There’s a bat here!”
“I see, I see, there’s two on this side too!”
“How do I get him out?!”
“Wait, wait, calm down!” Hilda pulled out one of the cloth bags and came over to me.
“Okay, the first step is to figure out which side of the net the bat flew in from. See this big hole here over his belly? That’s where you put the bag to support the little guy.” She placed the bat on the bag in her palm, and pinned him down firmly with her thumb on his back.
“See, this way he can’t bite you, you just let him bite the bag. Then you first free his legs -” she gently pulled the two hind legs and their wing membrane through the hole, “- and then you get the wings free one at a time. See, you get all the strings together and pull it over your thumb like this.” She pulled the net over the bat’s right wing, the animal gave a frantic shudder and freed his right half completely.
“See, he’s free on this side. Now you do the same thing on this side…” Hilda pulled and untangled gently until everything but the head was free of the clinging black thread.
“Now switch your grip, use the three-finger hold and get the head out.”
The three-finger hold was the proper way to hold a bat, and something I was familiar with: you had to pin the bat’s wings to his side firmly with the thumb and middle finger, and place your index finger at the back of his neck so he couldn’t move. Now the bat was free of the net and quite helpless as Hilda held him tightly and turned him over to sex him. Then she held him to the feeder so he could drink his fill.
“It’s good to feed them a bit, they’re a bit stressed with all the catching and handling.”
The bat put his tongue out and lapped briskly until his belly swelled like tiny, hairy balloon. Hilda slipped him into the bag, drew the string tight and hung him up next to the feeder. The bag flailed around desperately for a minute, then hung there, quivering.
“You think you can get the bats out now, Sam?” She cocked an eyebrow at me.
It wasn’t easy. Even as we had got the first bat out, several more had flown into the partially open net, and there were now at least five little brown balls, seemingly suspended in mid-air, twisting and struggling. Getting them out was the ultimate exercise in patience, a moment of complete and perfect Zen at the end of an extraordinarily trying evening. Inexperienced as I was, the bats slipped out of my grasp again and again and sank their needle-sharp teeth into my fingers every chance they got. But it was their well-being, not mine, that mattered. I couldn’t let the strings cut them, nor could I let them twist into the wrong position and hurt themselves. The world shrank to the size of a small brown bat, a little mouse with voluminous angel wings, and the forest fell away. There was no more mud, no more leaf-cutters in my boots, no insects in my mouth, no glittering spider, no rain, no knot, no racket of frog-calls. There was only the bat, the net and my fingers, working smoothly together.
Once I got my first bat free the world swam slowly back into focus and oh, what a bizarre world it was. The bats around us simply didn’t care that there was a huge knot in the net. They didn’t care that their comrades were shrieking from inside little cloth prisons. They didn’t even care about the two clumsy humans in their way, as they wove between us. All they cared about was the sugar-water in the feeder. It was the ultimate nectar-dispensing flower, a veritable holy grail of sweetness. They were lucky to get twenty millilitres of nectar a night and here was fifty times as much, ready for the taking. They weren’t going to let anything stop them, not us, not the rain, not the screams of their fellow bats. Luckily for us, the worst mist-net in the world still did. For every bat we freed another one trapped itself, and for half an hour we scrambled back and forth along the net and behind it, as the row of wriggling bags grew longer and longer.
Eight bats and a thousand bat-bites later we managed to clear the net and hastily put the ties on it before any more bats showed up. The leaf-cutters were gone, but the wolf-spider was still there, glinting at me every time I glanced in her direction.
“Okay, now we just check the bats again and let the males go!” chirped Hilda. She wasn’t the only one feeling perky. Now I had finally got the hang of mist-netting my mood had lifted miraculously. I looked at the row of twitching bags, and suddenly felt so exhilarated I could have run a marathon. The battle had been long and hard but we had won.
“We need four females, right? We have enough, right?”
We gathered our things, hung the bat-bags on Hilda’s handle-bars and slowly biked back. The frogs were still thronging the path, but of course, now that we were done with the forest, now that we had all the bats we needed, the rain had cleared up nicely and a crystalline moon was peeping through the gaps in the foliage.
Back in the flight cage we weighed the bats, hung RFID collars around their necks, entered their transponder numbers into our program and let them go. Within minutes they had found a dark corner to huddle into and we saw them no more that night.
Tomorrow we would come back, check our data, and check on our animals, but for now, there was the shower, the dinner, and the promise of bed while the gecko sang me to sleep and kept the watch. It wasn’t until I was nearly asleep that night that it sunk in: the whole evening had been my childhood dream come true. Twelve years ago I had read Gerald Durrell’s stories about catching animals in the wild, the discomfort, the pain, the exasperation, the mud, sweat and tears that went with it, and wondered how, despite it all, he made it sound like the most desirable job in the world.
Now I knew.
Shambhavi’s stories from the Costa Rican rainforest are published as a four-part series here on Amicable Scientists. This is part four; do check out the other parts as well!
Guest post written by Shambhavi Chidambaram.
Shambhavi (AKA Sam) is a biologist studying animal behaviour and neuroscience at the Humboldt University, Berlin. When she’s not chasing bats or running trails, she’s usually busy hunting for a perfectly-tailored humorous metaphor. Science writing for her is an art; she believes her work is done when anybody who reads her pieces has not only learned something fascinating but feels smarter in the process. While Sam mostly writes about biology and Open Science, she’s always keen for new ideas. You can follow her on Twitter at the handle @Quidestvita.