Sus ojos brillan rojo en la noche
San Crisanto crocodile expert Don Leonardo José with a just-caught specimen. A t-shirt is wrapped around its eyes to keep it calm.
Story and photos by Tess Moore ’23
Whenever I told someone that I was preparing to go to the Yucatán program in a few short months, I would be peppered with questions about whether I had any ideas for my independent project. My response was vague, but always the same: Something with crocodiles. That past spring, I had devoted most of my academic time to various herpetological field projects, with amphibians in Acadia National Park at Duck Brook and Otter Point, and a turtle marking census at Little Long Pond for the Land and Garden Preserve. It had always been a dream to work with crocodiles, and this fieldwork would be a good form of preparation. However, Maine is not the best study location if you want to work with anything large and scaly that doesn’t have a shell. While the Yucatán program wasn’t dedicated to this form of scientific study, its open-endedness and location in the range of two crocodile species led to a burning desire to somehow study them once I arrived.
Walking to my house in San Crisanto for the first time, I realized why I was here. Behind the carefully raked sand and coconut palms that made up my family’s backyard were the mangroves. Twisting roots and mats of glossy leaves hung over murky pockets of water, creating seemingly infinite hiding spaces for lurking reptiles. Vermiculated tree frogs squeaked from the tops of the trees, and emerged from the walls of the house in times of rain, sometimes falling from the ceiling and inciting terror. Once one landed on the dinner table to the chagrin of my host mother, who was terrified. I quickly picked it up and took it to the nearby mangroves. I found out quickly why the Spanish name for this amphibian is Rana lechosa, or milky frog, thanks to the thick white poison that it excreted. While I thought I washed my hands well, at some point I touched my eye and was up all night with tears and swollen eyelids.
I knew that there was a crocodile marking study in San Crisanto, but I did not know who performed it, funded it, or why they did it. I asked my family what they knew about the tagging. “Ah, lo he hecho tu Tío Mach con Don Leo.” My uncle had worked tagging the crocodiles in the past, working with a man named Don “Leo” Leonardo José, or more commonly known as Pito Loco. The next day, I biked to his house with my brother, and we introduced ourselves. After chatting for a while, he showed me some crocodiles that he had taxidermied, and I asked about the tagging. He lit up, and explained to me the whole process. The ejido, or local land government, conducted a monitoring study of the number of crocodiles within their borders. The economy of San Crisanto is dependent on ecotourism, thus the health of charismatic species such as crocodiles and flamingos is very important, as made evident by the many murals depicting them throughout the town. During the period in which the crocodiles are primarily in accessible canals and water levels are lower, Leo and two other helpers go out at night to capture them with a wire noose attached to a stick from a tiny rowboat, then weigh, measure, sex, and mark their tail scutes.
The pages of my notebook were filling up with information as my excitement mounted. However, the prospects of participating in the tagging seemed cut short when Leo mentioned that the study only took place every two years, and they had just done it last winter. I must have appeared visibly crestfallen, as Leo realized that I wanted to take part in this work rather than just gather information on it. “Pues, tengo ganas de hacerlo otra vez, y si puedes hablar con el comisario para recibir fondos, es posible que podriamos hacer el trabajo esta temporada.” If I were able to convince the town commissary to provide pay for the work and give us access to headlamps and a pickup truck, then Leo would be willing to do the work this year. I talked to my family about this, and they were excited at the prospect, but told me that the commissary wouldn’t give me the funding if I asked him first. They advised me that in order to get the survey approved, I would have to talk to Don Ines Jose Loria, the head of the ejido. He was more likely to say yes, and el comisario would almost surely agree if Loria did. After translating my CV into Spanish, I presented it to him at a meeting and explained my background and why I wanted to work on this study as part of my final project for the Yucatán program. After a couple of days, he told me yes, and we were able to start the following night.
Duct tape is used to safely secure this crocodile’s jaws. This individual was in water too shallow for the boat; it was caught by wading into the mangroves.
We turned the corner in the rowboat, a new stretch of the canal becoming visible under the dangling mangrove roots.
“¡Aita, aita!”
About 30 feet ahead of us, two bright red flashes appeared in the lights of our headlamps before silently slipping underwater. “Aita esta. D’espacio vamos adelante.” One would expect water filled with tannin-leaching leaves, swamp eels, and toe-biting water bugs as big as your palm to be murky and brown, but it was crystal clear thanks to the alkaline water belched from underground by a nearby cenote.
We advanced slowly, pressing with a long stick against the mud rather than rowing, until we saw it. Blending gentle against the muck, four feet of scutes black and green and brilliant. Leo lowered his lasso into the water until the metal noose rested gently around the beast’s thick neck. However, when he hauled the cord it didn’t set right, and the reptile twisted free, running along the riverbed and leaving a cloud of silt in its wake. I felt lost at that moment, but Leo knew what to do. We followed the trail of murk, and the scenario repeated itself twice before the noose held.
The best way to safely bring a crocodile into a tiny boat is to let it tire itself out. The same “death roll” that they use to dismember larger prey items is also a defense mechanism. The croc spun and spun at the surface, frothing the water into a storm. After what felt like ages, it became tired and gave a respite from movement.
“¡Pone la cinta, pone la cinta!” Miguel, my host father, held the roll of duct tape in his hand to wrap up the croc’s jaws and neutralize the threat of a bite, but not having done this work before, I was not sure what to do. While this was my first night out and I had told myself I would take the first experience to observe and avoid any potential injuries, I was tired of feeling useless and grabbed the crocodile’s snout, closing the jaws shut with my hand, leaving just enough time to put on the tape.
It wiggled free once again, and spun around a few more times before becoming tired enough that we could bring it into the boat with us, where it sprawled across the middle seat, taking it up and then some.
Measuring snout to tail length of a small crocodile captured by hand in the salt flats.
After weighing the hefty brute at 36 kilos, we loaded it into the back of the pickup truck and drove into town. This was not a particularly large crocodile, but it was big enough that the ejido did not want it in the waters that they passed dozens of tourists through each day (Crocodile attacks in the Yucatán peninsula are exceedingly rare, and there has never been one in San Crisanto). Three of the scutes on its tails were removed, indicating that this was a recapture and marking it as crocodile #68 out of the 233 already marked in the ejido’s territory.
An examination of the beast’s olive-green scutes confirmed that it was a Morelet’s crocodile (Crocodylus moreletii), the smaller and more common species of crocodile found in these waters, the other being the larger and more wide-ranging American crocodile, found from the Florida Everglades to both Caribbean and Northern Pacific South America.
Once we got it into the back of the pickup truck, I was tasked with keeping it calm while Leo drove us to an isolated area of swampland halfway between San Crisanto and the neighboring town of Telchac Puerto. This was not as difficult as I thought it would be, as the creature was exhausted from the battle. I felt sorry for it, blinded on a bed of dark plastic bouncing upon a gravel road. This was its second time being hauled from the water, but it must have been incredibly disorienting all the same. Were it up to me we would have released it back into the canals where we found it.
After what seemed like ages of barreling down the highway in the dark, we pulled over at a tunnel into the undergrowth lining the highway. It was cramped with thorny branches and growing over, without much space to move. Worried that there wasn’t access to the water, I got onto my belly and crawled in, to the dismay of all around me, who shouted, “Cuidado por las culebras!” People here were understandably very nervous about venomous snakes, such as the infamous viper wohl’poch. While I sadly never saw one in my time on the peninsula, I was once gifted a boa constrictor someone found while cleaning their house.
I was able to reach the edge of the water fairly quickly, snakes notwithstanding. After returning to the truck, we brought the croc as far as we could into the brush, and set it down gently. Leo was nervous that it would explode back to life once we removed the shirt covering its eyes, and advised us to stay back. He carefully removed the tape from its jaws with a pocketknife, and then yanked the shirt off and jumped back in one fluid motion. The croc just sat there in the wet grass, nostrils flaring as it breathed; the only signs of life. We waited, watching it for movement. Eventually its stubby legs moved and it pushed itself forward, tail dragging behind as it slunk into the dark tunnel, roots and branches embracing the old reptile as it returned to the brackish waters of its home in the mangroves.
Tess Moore ’23 shows a crocodile hatchling to some children while working on a project in San Crisanto, Yucatán.
