By John Pint

 
(If the video doesn't appear above, go to Toscano's Cave on YouTube)

When bat researcher Leonel Ayala invited me to visit a cave he had found overlooking Lake Chapala, I figured it had to be typical of every other cave I’ve seen in the area: a closet-size hole which only gets dark at night. However, when he casually added that he’d appreciate my help in surveying and mapping the place—which he called La Cueva de Toscano—I figured his cave might even turn out to be two or three closets long. Well, I was in for a big surprise.

One day Leonel and I picked up caver Luis Rojas and drove off towards the town of Jamay, which is located at the eastern end of Lake Chapala. We parked in front of a lakeside restaurant and Leonel went off to talk to the owner of the land on the other side of the highway. “We have permission to visit the cave,” he announced a little while later and off we went.

After working our way through a grapefruit orchard, we came to a high promontory overgrown by a giant amate fig tree whose tendril-like roots formed a bizarre kind of Chinese string curtain.

The trail took us to a higher point from which we could see the lake in all its glory. Yet a little higher, at an elevation of 1650 meters, we came to a fissure in the rock, two meters wide. “This is it,” said Leonel.

Aha, I thought: just a crack. That’s about all you can expect in volcanic conglomerate like this. But we took out our tape, compass and clinometer and began surveying.

Well, the floor of this crack was slanted upward at an angle of about 49 degrees and when we got up to the very top we found ourselves standing in the doorway of a big room eight meters high with horizontal passages going off in two directions.

“What?” I gasped. “Leonel, this looks like a real cave—why didn’t you tell us?” Leonel, however, was too busy watching the screen of his video camera to answer me. He had lit up the roof of the big room (which was in total darkness) with invisible infrared light and was watching the antics of the many bats roosting there. Zooming in on two of these playful creatures, we could see every one of their whiskers in perfect focus. Not only that, Leonel has a device which lowers the frequency of the bats’ voices to within human range, so we could all hear the chattering, twittering and whistles of the socializing, quarreling and love-making which was going on above us. What a show!

World's Fastest Bats

We learned that there are two kinds of bats living in this cave, both rather remarkable. One of them is Pallas’s Long-Tongued Bat (Glossophaga soricina), famous for having the fastest metabolism of any mammal in the world, similar to that of a hummingbird. The other is the Jamaican Fruit Bat (Artibeus jamaicensis), one of the world’s most efficient mammals in terms of food digestion. It processes its food in about 15 minutes. “I read about this cave in a book on Mexican bats,” said Leonel. “The author visited this cave decades ago.”

Leonel’s bat book is called Los Murciélagos de México by Bernardo Villa (UNAM 1966). So far this book has successfully led us to two caves we knew nothing about, so I would say the cavers of the world should look into sources like this for rediscovering long-forgotten caves!
  

While Leonel took notes on the bats’ behavior, Luis and I went off to survey the passage on the left, whose walls were slanted at a 51-degree angle. Here we spotted several flat spiders of the sort you’re more likely to find crawling on the rocks alongside Río Caliente.

Blood-Sucking Bugs

We also discovered a Chinche Hocicona on the wall, a blood-sucking “vinchuca” or Vampire Bug. This is the dreaded Triatoma infestans, which transmits trypanosomiasis or Chagas Disease, the infirmity which laid Charles Darwin in his tomb. These bugs have radar-like heat sensors in their antennae and subsist on a diet of blood. They’re most common in South American where they typically glide into your bedroom on air currents, inject a quarter-inch long needle into your neck and suck out up to seven times their body weight in blood. Then, uncouth visitors that they are, they defecate on your skin, thus depositing a parasite (Trypansoma cruci) which up to twenty years later, might give you a heart attack. As there is no cure for Chagas Disease, according to the University of Texas, I recommend you avoid sleeping “under the good old stars” in Mexico and that goes for sleeping in caves too. Believe it or not, we put up tents when we do sleep underground.

Fortunately, the Chinche Hocicona doesn’t bother people who are wide awake and moving around, so we weren’t worried and carried on our survey.

Mystery Tunnels

As soon as we crawled into the right-hand passage, we knew this cave was something out of the ordinary. We found ourselves in an almost square-shaped tunnel 75 centimeters wide by 85 high and perfectly straight. Normally this means you are in a man-made passage inside a mine, but this tunnel in Toscano’s Cave showed no sign of chiseling or chopping. We followed it for 12 meters to a room where you had to walk above a deep crack half filled with water, supporting your weight on nubs sticking out of a wall. That’s where I turned around, but climbers Luis and Leonel took over the survey.

On the other side of the water were passages heading left and right, and once again they were square-shaped crawlways like the first. The left branch ended abruptly after 27 meters, while the right-hand one curved around toward the cave’s entrance and actually passed underneath the entrance fissure, only to end at the foot of a nine-meter-high tube about a meter in diameter.

I was standing outside of and above the cave entrance when I suddenly saw Leonel’s head pop up right out of the ground. A weird cave indeed it turned out to be, with a total of 118 meters of passages, most of them nearly square in shape and about a meter high and wide…mighty suspicious, eh? Well, we are waiting for the experts to explain it all to us.