10-24-2020, 11:39 AM
1/2/2019: Part 6 -- The Swamp
Eyeshine
The first few times you go out on night-walks, you don't notice it much. All you see is a swathe of vegetation in your beam. But after you've done these night-walks a few times, you start to see more, and eventually you see the totality of the eyeshine. There's twinkling pinpricks of light wherever you look. Tonight I'm hyperaware of it, the eyeshine on the trunks, branches, ferns and fronds, on the decaying vegetable matter at my feet. There's hundreds of pinpricks wherever I look. They're spiders, with few exceptions. Not big ones, mind you. Not tarantulas. When you get down close to one, the pinprick resolves into two dots, or more, because spiders have nothing better to do than grow extra eyes. These are teensy-weensy spiders, working nightshift, preying on the tiniest of insects.
You don't see eyeshine in humans. At most you get red-eye, and only under very special circumstances. In flash photography, if the flash is insufficiently offset from the camera lens and the subject's pupils are wide open, the lens can capture the redness of the blood vessels in the back of the eye. It's a dull red, indicative of our poor night vision. But nocturnal animals are different. They have a retroreflector (apetum lucidum, "bright tapestry") behind the retina that reflects light back through the retina so the photoreceptors can get a second helping of photons. This is what gives them good night vision. And if you shine a bright light on the apetum lucidum, it acts like a mirror. That is the eyeshine you see in nocturnal animals. You've doubtless seen it with possums, raccoons, skunks, even housecats. Nocturnal bugs have a similar reflective adaptation.
Most of the pinpricks I'm seeing are indistinguishable, because they come from basically the same thing -- tiny spiders. But mixed in with them are some that are bigger, or differently hued, or they have an odd scintillation or cast, or they might even blink. Because mixed in with all those tiny spiders are other critters -- frogs, toads, beetles, scorpions, what have you. An expert can identify many insects and animals just by the character of the eyeshine. But I'm far from that level. All I've got going for me is curiosity. And that's what's driving me nuts right now. Because among all the eyeshines dotting trunks, branches, ferns and fronds, and speckling the ground at my feet, there are a few that are different, that stand out as unique. I'm itching to get up close to them to solve the mystery of what they are.
But this is not the night for that. Tonight we're after bigger game. We're going into a swamp.
The Swamp
Before we set off from the research station, Mohsin gathered us together to make certain we were properly attired and equipped. Headlamps are of course a necessity. The research station has maybe 8 sets of rubber boots available for use, but Mohsin doesn't recommend using them. They'll just fill with swamp water and become a drag on you, and could even pose a danger if you hit a deep spot. So, we're just wearing our normal shoes and socks. He recommends that we tuck our pantlegs into our socks. Likely to keep out the creepy crawlies. Things like water snakes, poison dart frogs, diving spiders... I wonder if there will be leeches. Anyway, we tuck our pantlegs into our socks.
I bought two waterproof backpacks for this trip. It was recommended by several rainforest travel sites. We've used them on boat excursions, but they were never needed. But tonight? Tonight I've got my waterproof backpack strapped on.
When everyone is ready, Mohsin leads us across the clearing towards rainforest, our beams dancing about. I'm following close behind Mohsin and notice something. "Mohsin? Why don't you have your pantlegs tucked in?"
"So I can look cool as long as possible," he casts back without missing a beat. He says he'll tuck them in when we get to the swamp.
Which makes a lot of fashion sense.
Mohsin leads, with me close behind. Then comes Ian and Mina, the Swedes Olaf and Magnus, the resourceful Indian Saurabh (who I haven't talked about much), and then there's Paula, who at the last second decided to come along. We're on a trail I should know by now, then we split off on another, then onto what I think is a new trail.
As we progress, I'm disheartened to realize my headlamp is weak. I tested it in our room and it seemed okay. But I should have put in new batteries just to be safe. Still, it's not easy to find new batteries in the dark mess of our room.
We haven't gone far, maybe a 15 or 20 minute walk. Then Mohsin slows to a stop and points aside. "This is it," he says.
It's hard to see the swamp, or its extent. I don't think it's very big, maybe 30 by 30 feet, house-sized, but jigsawed into the rainforest. There's a good-sized tree on a tiny island mass near its center. The surface is choked with muck and leaves, with dead limbs flaring up. That's the general impression, as we only see it piecemeal as our headlamps excavate it in sweeping pans.
Mohsin starts into the undergrowth to the right of the island tree, but a log and thick brush drives him back. "Let's go around the other way," he says, changing course.
I follow Mohsin's lead, sinking in to my ankles, calves, ever deeper. I hear the others sinking in behind me. It's treacherous going, as the bottom is slick and uneven, fraught with roots and snags ever bent on tripping you. The swamp is choked with muck and brambles and tangles of vegetation, and lurking among these, poised and ready to pounce, are big predatory spiders. It's the rare spider that creeps me out. These creep me out. They're big, poised, as if ready to pounce. I don't know what type these are, and whether they're at all venomous, but they look strong and agile, covered in fine hairs that enable them to run across the surface or form air bubbles for breathing while diving beneath the surface. Maybe they have webs too. But I don't recall seeing any.
Here's a photo that approximates the big fishing spiders we were seeing:
[NOT MY PHOTO: Giant fishing spider, Ancylometes bogotensis]:
![[Image: uc?export=view&id=1eQWmpEKjdmdMhaMznGZE80WJmq_bLII_]](https://drive.google.com/uc?export=view&id=1eQWmpEKjdmdMhaMznGZE80WJmq_bLII_)
I'm keeping up, but feeling increasingly unstable. In all our past excursions, no matter how tough the terrain, I've found ways to compensate for my bad hips. Mostly I use muscle tension as a substitute for missing cartilage, but this also involves properly orienting myself to make this possible. I've gone up and down the steep gully inclines by turning to be strongest and most flexible where necessary. But here all directions are precipitous. It's like being on stilts on ice that is uneven, and cluttered, and oh by the way I'm blind. I'm tensing all the muscles around the hips in all directions to keep from splaying apart, which is exhausting. It's a very sobering predicament. I wanted so badly to go into a swamp, and now here I am, all but helpless.
I'm up to my knees now, then to mid-thigh. My feet slide about on an uneven bottom, and my shins hit a branch. I almost fall over. I'm twitching, overcontrolling, awaiting the next surprise.
Everyone is well into the swamp now, their headlamps sweeping across the muck. They keep catching eyeshine, those tiny pinpricks that are small spiders, but also some bigger things, like frogs and who knows what else.
I notice a slight commotion. Olaf and Magnus are near the tree on its tiny island. It's shallower there. Olaf is waving his hands about, knocking something away. Headlamps converge on his antics to show a couple of wasp-like things dive-bombing from a limb overhead. He might have gotten stung, but I'm not sure.
Mohsin is panning the edge of the swamp, and his beam catches something: two reddish orbs, very reflective, just above swamp level. "Caiman," Mohsin whispers. The red orbs are all you can see. But it's a caiman, and it's on the bank. Ian quickly locks onto it and starts forward, but Mohsin suggests a more circuitous route on the bank.
I'm in an unfortunate spot. The trunk of that island tree is blocking my view. I wade left to get clear of it, but the swamp gets deeper. I'm up to my waist now. Meanwhile, Ian has climbed onto the bank and is circling in from the right. Then my shin hits another bottom branch, and I skid and sag backward. I fight to stay erect, but am straining. That's it. I'm done moving. I don't want to make a commotion and spoil things for Ian.
Ian is almost there. He's closing in on the spot. Then I hear a splash. It isn't me. The caiman got spooked and dove into the swamp. All seems lost. Still, Ian remains intent on the spot. Suddenly, he just falls forward into the swamp. There's all kinds of splashing, then things get quiet.
"Did you get it?" Mohsin asks.
Ian stands up, hugging something. "Yeah."
Mohsin is surprised he got it, especially after it spooked. But Ian says he could just barely see it sitting on the bottom. Apparently it thought itself safe down there. Mohsin makes sure he's got a proper grip on it. Ian has caught small ones before in other parts of the world, so he pretty much knows what he's doing. Then we all congregate in the middle of the swamp, and while Ian grips the caiman, Mohsin points out several interesting features. It's a spectacled caiman. The bony ridge between the eyes makes it appear to be wearing glasses -- or so it's said. I don't have a camera with me, so once more I'll borrow from the web:
[NOT MY PHOTO: Spectacled Caiman]
![[Image: uc?export=view&id=1PTRwm-HVjRmUWGLhzhHyG-WXgh0WEtlY]](https://drive.google.com/uc?export=view&id=1PTRwm-HVjRmUWGLhzhHyG-WXgh0WEtlY)
Spectacled caiman get up to seven feet long, but that's very rare. Four or five feet is more typical. This one is three, maybe three and a half feet long. If female, it's pretty much an adult. If male, it's got a bit more growing to do. It's the biggest caiman Ian has dealt with.
Mohsin encourages everyone to feel its scales. I take my turn. The scales vary in size and texture depending on where on the body they are. The teeth are a bit scary, and Ian had guts pouncing on it like he did. Then Mohsin gives instructions on how to safely grip the caiman, and cautions people to be ready for a sudden powerful thrashing. There follows a careful hand-around to everyone in the party. I skip this, telling Mohsin that if it thrashes, I'm not certain I can stay upright.
When it comes Paula's turn, I have concerns. She grips it properly, but I'm just not seeing the firmness. Mohsin must see this too, because he stresses how powerful a thrashing caiman can be, and repeats this a couple times to her, and that the thrashing can come without warning. I'm not so much concerned with the caiman escaping, as it will almost certainly head away from us. But those teeth... If it thrashes, those teeth don't have to bite. If they make contact with any flesh...
The moment of truth comes and goes. Paula holds the caiman and nothing happens. Everyone has taken a turn (excepting me), and not once has the caiman thrashed. Ian again holds the caiman, and now it's time for us to leave the swamp. Mohsin says we'll release the caiman once we're all out.
As we all start charting courses out, two main avenues avail themselves. One is more direct, but goes deep. The other is more roundabout, but shallower, though it's infested with giant fishing spiders. "Take your pick," someone says. "Deep swamp, or big spiders."
I choose to take the shallower route. As I'm wading among all the big spiders lurking in their little territorial coves, there's chatter among those going deep. Olaf and Magnus have spied a poison dart frog. That's not all that surprising where we're at, but this one isn't tiny; it's the size of a regular frog. They've never seen such a thing. Not that they're able to catch it, and soon it's gone.
Eventually we all reach solid ground and gather near the trail, except for Ian, who is crouched five feet from the swamp, preparing to set the caiman down.
Mohsin tells us to watch how fast it scrambles into the swamp. Ian puts it down and jumps clear. The caiman doesn't move. Stomping near it does nothing. Mohsin ventures close to check it out. It seems okay. Ian then moves it closer to the swamp. Still nothing. Mohsin and Ian have never seen such a docile reaction. I suspect the caiman is in a state of shock. Ian is a bodybuilder. I think he so overwhelmed the caiman catching it that it can't believe it's still alive. Mohsin, crouched down with a hand on a log, jumps up. "Look, guys. I'm seeing bullet ants here. Let's finish up and move out." Ian finally picks up the caiman and places it in the edge of the swamp. Only then does to caiman come to life and dive away.
Eyeshine
The first few times you go out on night-walks, you don't notice it much. All you see is a swathe of vegetation in your beam. But after you've done these night-walks a few times, you start to see more, and eventually you see the totality of the eyeshine. There's twinkling pinpricks of light wherever you look. Tonight I'm hyperaware of it, the eyeshine on the trunks, branches, ferns and fronds, on the decaying vegetable matter at my feet. There's hundreds of pinpricks wherever I look. They're spiders, with few exceptions. Not big ones, mind you. Not tarantulas. When you get down close to one, the pinprick resolves into two dots, or more, because spiders have nothing better to do than grow extra eyes. These are teensy-weensy spiders, working nightshift, preying on the tiniest of insects.
You don't see eyeshine in humans. At most you get red-eye, and only under very special circumstances. In flash photography, if the flash is insufficiently offset from the camera lens and the subject's pupils are wide open, the lens can capture the redness of the blood vessels in the back of the eye. It's a dull red, indicative of our poor night vision. But nocturnal animals are different. They have a retroreflector (apetum lucidum, "bright tapestry") behind the retina that reflects light back through the retina so the photoreceptors can get a second helping of photons. This is what gives them good night vision. And if you shine a bright light on the apetum lucidum, it acts like a mirror. That is the eyeshine you see in nocturnal animals. You've doubtless seen it with possums, raccoons, skunks, even housecats. Nocturnal bugs have a similar reflective adaptation.
Most of the pinpricks I'm seeing are indistinguishable, because they come from basically the same thing -- tiny spiders. But mixed in with them are some that are bigger, or differently hued, or they have an odd scintillation or cast, or they might even blink. Because mixed in with all those tiny spiders are other critters -- frogs, toads, beetles, scorpions, what have you. An expert can identify many insects and animals just by the character of the eyeshine. But I'm far from that level. All I've got going for me is curiosity. And that's what's driving me nuts right now. Because among all the eyeshines dotting trunks, branches, ferns and fronds, and speckling the ground at my feet, there are a few that are different, that stand out as unique. I'm itching to get up close to them to solve the mystery of what they are.
But this is not the night for that. Tonight we're after bigger game. We're going into a swamp.
The Swamp
Before we set off from the research station, Mohsin gathered us together to make certain we were properly attired and equipped. Headlamps are of course a necessity. The research station has maybe 8 sets of rubber boots available for use, but Mohsin doesn't recommend using them. They'll just fill with swamp water and become a drag on you, and could even pose a danger if you hit a deep spot. So, we're just wearing our normal shoes and socks. He recommends that we tuck our pantlegs into our socks. Likely to keep out the creepy crawlies. Things like water snakes, poison dart frogs, diving spiders... I wonder if there will be leeches. Anyway, we tuck our pantlegs into our socks.
I bought two waterproof backpacks for this trip. It was recommended by several rainforest travel sites. We've used them on boat excursions, but they were never needed. But tonight? Tonight I've got my waterproof backpack strapped on.
When everyone is ready, Mohsin leads us across the clearing towards rainforest, our beams dancing about. I'm following close behind Mohsin and notice something. "Mohsin? Why don't you have your pantlegs tucked in?"
"So I can look cool as long as possible," he casts back without missing a beat. He says he'll tuck them in when we get to the swamp.
Which makes a lot of fashion sense.
Mohsin leads, with me close behind. Then comes Ian and Mina, the Swedes Olaf and Magnus, the resourceful Indian Saurabh (who I haven't talked about much), and then there's Paula, who at the last second decided to come along. We're on a trail I should know by now, then we split off on another, then onto what I think is a new trail.
As we progress, I'm disheartened to realize my headlamp is weak. I tested it in our room and it seemed okay. But I should have put in new batteries just to be safe. Still, it's not easy to find new batteries in the dark mess of our room.
We haven't gone far, maybe a 15 or 20 minute walk. Then Mohsin slows to a stop and points aside. "This is it," he says.
It's hard to see the swamp, or its extent. I don't think it's very big, maybe 30 by 30 feet, house-sized, but jigsawed into the rainforest. There's a good-sized tree on a tiny island mass near its center. The surface is choked with muck and leaves, with dead limbs flaring up. That's the general impression, as we only see it piecemeal as our headlamps excavate it in sweeping pans.
Mohsin starts into the undergrowth to the right of the island tree, but a log and thick brush drives him back. "Let's go around the other way," he says, changing course.
I follow Mohsin's lead, sinking in to my ankles, calves, ever deeper. I hear the others sinking in behind me. It's treacherous going, as the bottom is slick and uneven, fraught with roots and snags ever bent on tripping you. The swamp is choked with muck and brambles and tangles of vegetation, and lurking among these, poised and ready to pounce, are big predatory spiders. It's the rare spider that creeps me out. These creep me out. They're big, poised, as if ready to pounce. I don't know what type these are, and whether they're at all venomous, but they look strong and agile, covered in fine hairs that enable them to run across the surface or form air bubbles for breathing while diving beneath the surface. Maybe they have webs too. But I don't recall seeing any.
Here's a photo that approximates the big fishing spiders we were seeing:
[NOT MY PHOTO: Giant fishing spider, Ancylometes bogotensis]:
I'm keeping up, but feeling increasingly unstable. In all our past excursions, no matter how tough the terrain, I've found ways to compensate for my bad hips. Mostly I use muscle tension as a substitute for missing cartilage, but this also involves properly orienting myself to make this possible. I've gone up and down the steep gully inclines by turning to be strongest and most flexible where necessary. But here all directions are precipitous. It's like being on stilts on ice that is uneven, and cluttered, and oh by the way I'm blind. I'm tensing all the muscles around the hips in all directions to keep from splaying apart, which is exhausting. It's a very sobering predicament. I wanted so badly to go into a swamp, and now here I am, all but helpless.
I'm up to my knees now, then to mid-thigh. My feet slide about on an uneven bottom, and my shins hit a branch. I almost fall over. I'm twitching, overcontrolling, awaiting the next surprise.
Everyone is well into the swamp now, their headlamps sweeping across the muck. They keep catching eyeshine, those tiny pinpricks that are small spiders, but also some bigger things, like frogs and who knows what else.
I notice a slight commotion. Olaf and Magnus are near the tree on its tiny island. It's shallower there. Olaf is waving his hands about, knocking something away. Headlamps converge on his antics to show a couple of wasp-like things dive-bombing from a limb overhead. He might have gotten stung, but I'm not sure.
Mohsin is panning the edge of the swamp, and his beam catches something: two reddish orbs, very reflective, just above swamp level. "Caiman," Mohsin whispers. The red orbs are all you can see. But it's a caiman, and it's on the bank. Ian quickly locks onto it and starts forward, but Mohsin suggests a more circuitous route on the bank.
I'm in an unfortunate spot. The trunk of that island tree is blocking my view. I wade left to get clear of it, but the swamp gets deeper. I'm up to my waist now. Meanwhile, Ian has climbed onto the bank and is circling in from the right. Then my shin hits another bottom branch, and I skid and sag backward. I fight to stay erect, but am straining. That's it. I'm done moving. I don't want to make a commotion and spoil things for Ian.
Ian is almost there. He's closing in on the spot. Then I hear a splash. It isn't me. The caiman got spooked and dove into the swamp. All seems lost. Still, Ian remains intent on the spot. Suddenly, he just falls forward into the swamp. There's all kinds of splashing, then things get quiet.
"Did you get it?" Mohsin asks.
Ian stands up, hugging something. "Yeah."
Mohsin is surprised he got it, especially after it spooked. But Ian says he could just barely see it sitting on the bottom. Apparently it thought itself safe down there. Mohsin makes sure he's got a proper grip on it. Ian has caught small ones before in other parts of the world, so he pretty much knows what he's doing. Then we all congregate in the middle of the swamp, and while Ian grips the caiman, Mohsin points out several interesting features. It's a spectacled caiman. The bony ridge between the eyes makes it appear to be wearing glasses -- or so it's said. I don't have a camera with me, so once more I'll borrow from the web:
[NOT MY PHOTO: Spectacled Caiman]
Spectacled caiman get up to seven feet long, but that's very rare. Four or five feet is more typical. This one is three, maybe three and a half feet long. If female, it's pretty much an adult. If male, it's got a bit more growing to do. It's the biggest caiman Ian has dealt with.
Mohsin encourages everyone to feel its scales. I take my turn. The scales vary in size and texture depending on where on the body they are. The teeth are a bit scary, and Ian had guts pouncing on it like he did. Then Mohsin gives instructions on how to safely grip the caiman, and cautions people to be ready for a sudden powerful thrashing. There follows a careful hand-around to everyone in the party. I skip this, telling Mohsin that if it thrashes, I'm not certain I can stay upright.
When it comes Paula's turn, I have concerns. She grips it properly, but I'm just not seeing the firmness. Mohsin must see this too, because he stresses how powerful a thrashing caiman can be, and repeats this a couple times to her, and that the thrashing can come without warning. I'm not so much concerned with the caiman escaping, as it will almost certainly head away from us. But those teeth... If it thrashes, those teeth don't have to bite. If they make contact with any flesh...
The moment of truth comes and goes. Paula holds the caiman and nothing happens. Everyone has taken a turn (excepting me), and not once has the caiman thrashed. Ian again holds the caiman, and now it's time for us to leave the swamp. Mohsin says we'll release the caiman once we're all out.
As we all start charting courses out, two main avenues avail themselves. One is more direct, but goes deep. The other is more roundabout, but shallower, though it's infested with giant fishing spiders. "Take your pick," someone says. "Deep swamp, or big spiders."
I choose to take the shallower route. As I'm wading among all the big spiders lurking in their little territorial coves, there's chatter among those going deep. Olaf and Magnus have spied a poison dart frog. That's not all that surprising where we're at, but this one isn't tiny; it's the size of a regular frog. They've never seen such a thing. Not that they're able to catch it, and soon it's gone.
Eventually we all reach solid ground and gather near the trail, except for Ian, who is crouched five feet from the swamp, preparing to set the caiman down.
Mohsin tells us to watch how fast it scrambles into the swamp. Ian puts it down and jumps clear. The caiman doesn't move. Stomping near it does nothing. Mohsin ventures close to check it out. It seems okay. Ian then moves it closer to the swamp. Still nothing. Mohsin and Ian have never seen such a docile reaction. I suspect the caiman is in a state of shock. Ian is a bodybuilder. I think he so overwhelmed the caiman catching it that it can't believe it's still alive. Mohsin, crouched down with a hand on a log, jumps up. "Look, guys. I'm seeing bullet ants here. Let's finish up and move out." Ian finally picks up the caiman and places it in the edge of the swamp. Only then does to caiman come to life and dive away.