In the province of Puntarenas, near the Gulf of Nicoya in western Costa Rica, there is a legend about an evil creature that preys on the minds of men. Several years ago, I was conducting field research in a mangrove swamp there. I lived with a family that owned the only bar in a sparsely settled community that stretched for two miles along a road that ended at a sugar cane distillery, a biological research station, and a thin strip of white sand beach called Playa Blanca.

It was in the bar El Huevo that I first heard the story of La Mona. Don Marvín was my host and his brother Pepé was a regular visitor on the weekends. Pepé was the black sheep of the family. He had nearly lost himself in the seductive grasp of drugs and high stakes poker. But on the darkest day of his life, while mired in miserable pain and sorrow, Pepé stumbled into a Baptist church where he says he was born again. His family could forgive him for the drugs, the women, and the gambling, but it was difficult for Don Marvín and his wife Donna Graciela to fully accept a family member that was non-Catholic. In fact, they hardly ever spoke to Pepé. His regular weekend visits were tolerated only because of the brand name clothing, perfume and electronics he sold from the bed of his battered pick-up truck. In exchange for low prices on these items, Don Marvín and Donna Graciela gave Pepé a place to stay and lunch on weekends. Pepé kept prices low by smuggling the goods up from Panama. Pepé said he would work the black market only until there was enough money to build a new Baptist church in his hometown of Golfito.

After Pepé told me his story of spiritual salvation, I told him about my first and last time in a Baptist church. When I was six, I had a friend that took me to the McKenzie River Baptist Church in the sticks of Oregon, where I grew up. After surviving a fire and brimstone sermon that seemed to last an eternity, I left the church with tears in my eyes and the strong conviction that I would never go back. And I never did. But years later the experience helped me form a bond in Costa Rica. After discovering that I had once been to a Baptist church and was also non-Catholic, Pepé decided that we should become friends. So, on the days when Pepé came to visit, he insisted that we eat lunch together.

After one of our lunches, I asked Pepé if he knew any local legends. Pepé's jovial, fat-faced smile took the shape of a frown. He looked over his shoulder, and even though he was Baptist, he made the Catholic sign of the cross.

He said, "There is the story of La Mona. But it is a thing we almost never speak of." He looked me right in the eye, and practically whispering, he said, "La Mona is half monkey and half woman. It lives in the forest and only appears on the darkest of nights. If a man is walking alone at night and he hears the laughter of La Mona he better run. At first it sounds like the laughter of a child, then, as La Mona approaches, the laughter becomes hysterical and terrifying. And if the unlucky soul can not escape, La Mona touches him on the head, and he becomes insane."

I asked Pepé if he knew anyone who had seen the creature. He said his own uncle had been touched by La Mona and had lost his mind. I asked Don Marvín's oldest son Chi-Chi about La Mona and he said it was merely a legend, yet none of Don Marvín's three sons would walk alone at night.

I liked to kid Pepé and Chi-Chi about La Mona. Stifling my laughter, I would say, "Hey Chi-Chi, where is La Mona tonight? Pepé, do you think La Mona is hungry?" Neither man ever answered. Pepé pretended he didn't hear me and Chi-Chi just walked away. I thought it was a joke - half monkey half woman swinging through the trees with an hysterical laugh, preying on men's sanity - but one dark night, after a month of intense field work, I too learned to fear La Mona.

Every day, I rode a bicycle two miles to the research station, picked up my gear and walked another mile and a half to my study site. The study site was on the edge of a large patch of mangrove. To reach it, I had to walk along Playa Blanca, swim across a small inlet, and pick my way along a sliver of rocky shoreline. At low tide the crabs hid beneath rocks at the water's edge or vanished in the tangle of mangrove roots. During high tide, this particular species of crab, the Eastern Pacific mangrove crab, would seek shelter from the rising sea on the barnacle encrusted trunks and gnarled limbs of the mangrove trees. If the crabs lingered too long beneath the murky water, they risked being eaten by snapper and puffer fish. Above water, however, the crabs risked being picked apart by birds or being captured and marked by me. I was studying their behavior patterns. I wanted to know if these crabs were free roamers or tended to stay on one tree throughout a molting cycle. For two months, I made observations at both low and high tides.

I watched crabs shovel muck from mangrove roots into their mouths, using their claws like spoons. I saw them fight each other and scurry from birds. But mostly, I observed them as they silently sat still, perched on a branch or laying flat against a mangrove trunk. I didn't want to startle them or disrupt their daily patterns, so when the crabs were still, I was still. In the intense tropical heat I would sometimes sit for hours, watching and recording their movements. I would daydream of ice water, cold mountain streams, and sparkling snowfields. Every now and then, I watched with envy as one of the fishermen sped by in a skiff. The fishermen warned me of crocodiles and caimans, they said they had seen them near the study site. But the crocodiles stayed further down the coastline, where the cool freshwater rivers emptied into the gulf. Occasionally, a dead puffer fish would wash up along shore, and once I saw a dead giant eel with huge fangs. Another time I saw a gang of vultures feasting on a rotting sea turtle that had washed up on the rocks. Its legs were tangled in a nylon rope, which had caused it to drown. There was plenty of down time in the mangrove to ponder the cycle of life and death and to appreciate the rhythm of the tides.

My days revolved around high tide. That's when the action started. It was then that I would slip into the muddy water up to my chin and silently capture and mark crabs. But one of the flaws in my study was that I had neglected to observe crab activity at night. So one night after dinner at the bar, I pulled on my only pair of jeans and donned my headlamp. Chi-Chi and his father Don Marvín were shocked.

"What, are you crazy?" said Don Marvín.
"You can't go out at there at night. It's dangerous in the mangrove at night," said Chi-Chi.
"It's dark. You will lose your way!" said Donna Graciela.

I flicked on my headlight and assured my hosts that I'd be back in three hours. I tried to explain how important it was that I capture and mark several crabs during that night's high tide. Donna Graciela begged me not to go, but seeing that that I could not be swayed, she finally said, "Que Dios le acompañe." May God accompany you.

It was a fine night and it felt good to be away from the bar. For weeks, I had been suffering through hot and muggy nights. Although I never drank, I spent my nights in the bar fighting mosquitoes and listening to drunk fisherman argue and tell stories. On a good night, they would sing to each other or grab me by the arm and mumble something at me like life depended on it. But lately, the mosquitoes had taken control of the bar, and the fishermen had found something else to spend their money on. As I pedaled the bicycle to the beach, I could see the low glow of cooking fires in several homes just off the road. The cinnamon smell of carob and mango trees floated on a gentle breeze and a million stars sparkled overhead. It felt good to be alive. But then I heard it, and the feeling changed.

It reminded me of how a day changes along the Gulf of Nicoya. As soon as the sun rises the day seems to meander at a slow and leisurely pace. But late in the afternoon there is a moment when time shifts towards twilight and eventual darkness. It happens quickly and crisply, like chalk snapping. I first noticed the phenomenon while resting in a rocking chair for several hours. The intensity of the moment startled me and forced me to rise from the chair. But this time it wasn't the day that changed. It was my state of mind.

As I approached the end of the road, the strange sound became louder. At first I thought it was a house cat, and I fruitlessly racked my brain to try and remember if I had ever seen a cat along the beach or in the mangrove. But I couldn't recall seeing one in the entire community. I hid the bicycle near a fence next to the dirt road that led to the beach. To the left there was a remnant of the tropical dry forest that had existed before the land was cleared for cattle. In the daylight, iguanas would bask in the sun by the road at the edge of the forest and seek cover among brown fallen leaves and branches. At night, twisted vines hung from the trees like lecherous old fingers. When they moved in the wind, the vines groaned a little and the leaves rasped. On that dark night there were strange shapes in the forest so I hurried toward the beach. But as I approached Playa Blanca, I heard the odd sound again. There was the whisper of the gentle waves lapping against the sand, and that noise. It was faint, but as I walked along the beach, I recognized the soft sound of a child's laughter.

I had walked this same beach twice a day for a month, and during that entire time I had only seen two other people there - and not a soul in the mangrove. It seemed illogical that a child would be playing on the beach at night, so I considered La Mona. Pepé said La Mona stalked at night. He told me not to go out alone after dark. He told me to run if I heard it. He said La Mona could steal my sanity, that I would be trapped in fear. What if the legend was true? I heard it again, children's laughter, and it was closer now. I felt like I was stepping into a dream - a really bad dream. Fear gripped me. My stomach churned. I held my breath, but I could not stop walking forward towards the laughter. My mind would not allow me to believe in La Mona, yet my heart pounded wildly. If the laughter changed to a hysterical cackle, I planned to sprint back to the bar as fast as possible.

The laughter was coming from a cluster of trees at the far end of the beach, just before the entrance to the mangrove. I shined my light in the direction of the sound. I saw two little kids playing in the sand with a plastic bucket, and they were laughing. Beyond them, sitting on the tailgate of a truck, were a man and a woman. I said "hello" as I walked by. I didn't ask them why they were hanging out at the beach so late at night, and they didn't ask me why I was practically running toward the mangrove swamp.

As I walked along the rocks that night, I felt jittery and hollow. Several minutes passed before I noticed the sound of barnacles crunching below my feet. It was low tide. Low tide? I was sure it would be high tide. Slowly, it occurred to me that I had already captured crabs earlier in the afternoon, and the tide wouldn't be high enough to capture and tag again for another six hours. The walk to the mangrove and my fear of La Mona had been for nothing. It seemed the long, sun drenched days had finally gone to my head - I had forgotten an entire afternoon's worth of work and had been shaken to the core by the laughter of kids at play. The shadow of La Mona had touched my heart, and for at least a brief moment the legend had been true.

By the time I got back home, the bar was almost closed. Don Marvín was happy to see me.
"How did it go?" he said.
"It was very interesting," I said. "I'll tell you about it tomorrow. I've got to lie down." I was exhausted.

The next morning Pepé was at the bar and I told him that I had heard laughter on the beach, and that at first I thought it might be La Mona. I smiled after sharing my story. Pepé must have thought I was poking fun at him because he just shook his head and walked away. We never spoke of it again.

Eventually, I returned to the United States and forgot about La Mona. But five years ago, I went completely insane. I lost my mind and was forced to spend five days on a mental ward. By the grace of God, friends, and family, I have recovered. But not a day has passed that I fail to ask myself what happened. Touched by La Mona is as good an answer as any. If you're ever down in Costa Rica near the Gulf of Nicoya at night, my humble advice is to stay at the bar. Drink a beer, toast La Mona. Above all, trust the locals - do not test their legends.

Questions?
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