Cenotes: An Ecology Lesson (Mexico - Part 5)

31 December 2011

Happy End of the World! Well, not really. Our Mayan guides at Chichen Itza explained that the end of the Mayan Long Count would be December 21 (or 22?), 2012. But that would just start another counting cycle, and it was really no big deal, except they planned to market the hell out of it this year to earn some extra pesos.

 [Interesting etymological note: “Yucatan” is the name of this peninsula and one of the Mexican states of the region. 500 years ago, when Cortez’s men used Spanish to ask the local Mayans the name of this place, they repeatedly answered “Yucatan! Yucatan!” and so it came to be known. Yucatan means “I don’t understand” in Mayan.]

There are no rivers in the Yucatan. No proper rivers that you can swim, fish, or paddle a canoe in, anyway. This seems a bit odd, considering it rains plenty here, with the southern parts approaching tropical rain forest (or tropical “dry/seasonal” forest, more exactly). But when the water falls from the sky, the ground doesn’t stop it. The whole Yucatan peninsula is made up of limestone. It’s karst country, to use the proper geological term.  [“Karst” was first named in Slovenia, another wonderful place we visited in 2011 with plenty of turquoise water and nifty caves.]

When rain falls through the sky, it absorbs carbon dioxide from the atmosphere, and some of the water and C02 combine to form carbonic acid, which is why rain water is a little bit acidic naturally, even without man-made pollution making it worse.  The acidic rainwater reacts with the limestone, dissolving it. The rain eats the rock. In areas with lots of limestone (“karst country”), the water seeps into the ground much more so than in many other areas, and travels in underground rivers. As the underground rivers dissolve the surrounding rock, you get caves. Sometimes the river eats away too much of the roof of the cave, and it collapses, giving you a sinkhole, or as they are known in the Yucatan, cenotes (“seh-NO-tays”).

The lack of surface rivers means that there is very little sediment pouring into the sea, meaning the water is generally very clear (high visibility), which is one reason why the Meso-American reef system (2^nd longest in the world, I think) is such a popular snorkeling and diving location. Besides the reef off-shore, another diving/snorkeling location that is very popular in this region are the cenotes themselves. There are thousands of cenotes across the Yucatan. They were the basis of the great Mayan civilization, and all major cities had one or more cenotes. Some of them are large (several hundred meters across), many of them are deep (we swam in one that is 90m deep), and they all generally have steep sides or even sides that angle out from the shore as you go down (the reverse of a regular lake), meaning the surface area at the bottom is much more than the top. The water is usually very clean (unless they have been abused by humans) and startlingly clear.

We snorkeled in Cenote Azul near the southern Yucatan town of Bacalar (which is also on a 60 km long freshwater lake – very beautiful). It had a little restaurant on the side, but people were surprisingly good about observing the no littering rule, and they also tell you not to wear sunscreen or bug spray into the cenote for water quality (hard to say if people were observing this rule).

No picture from above can do the color of this water justice, but this picture at least shows how big this cenote was.

The water was refreshing. It felt clean. I like swimming in fresh water so much more than salt water. From the outside, I snickered a bit about the “Blue Cenote” monicker, as it didn’t seem particularly blue to me (maybe it was the low angle of the light). But when I got in…wow!

The water was so clear, it was hard to remember it was even there. My hands and toes and in front of my eyes seemed to just be floating there in nothingness (well, because you’re less buoyant in freshwater, I had to work pretty hard to “float,” but that’s another story.). There wasn’t an abundance of fish, but the fish that were there were very easy to watch, including lots of little tiny fish about 1 inch long and only maybe ¼ inch wide that were shiny and were mouth breathing at the surface, it appeared. When I lifted my head above the water, you couldn’t see the fish at all. There was a leaf fallen from the tree, yellow and rust colored, suspended in the water column, spinning in the light. It was mesmerizing. The fact that you couldn’t see the bottom (it was almost 300 ft/ 90 m deep!!!) and it was so clear really heightened the effect of floating in space.  This particular cenote was generally cylinder-shaped, like a well, both very large (250 m across, maybe) and deep. The water was very near top of the geological depression (some cenotes are more hole and less lake), and the walls were thick with vegetation above the water line. The roots of the trees went down underwater along the outside of the rock 20-30 feet. Below that, there was nothing to see but the abyss.

Shannon didn’t like the cenote as much as me. Swimming over the abyss, with so much down below, was unnerving, and not being able to float as well in the freshwater didn’t help. So she had somewhat mixed feelings about the whole thing, but I loved it, and insisted that we visit another cenote the next day, on our drive back to Cancun.

The two most famous cenotes around Tulum are Gran Cenote and Dos Ojos. Dos Ojos (“Two eyes”) cenote is part of a cave system that extends tens of miles, and is apparently one of the longest systems in the world. It sounds like an incredible scuba dive, but my PADI certification is rusty and I don’t want to refresh it with cave diving, generally considered some of the most risky kind of diving you can do. You can snorkel there too, but without an underwater light I don’t think it would be that interesting (almost no natural light, I’m told), and I didn’t have time to rent a light from a dive shop. Gran Cenote was rumored to be friendlier to snorkelers and provide a better natural environment.

We accidently avoided paying the 100 peso entrance fee by parking in the commercial lot (for dive tours and tour buses). I guess sometimes it does pay to be a stupid gringo. This place was pretty crowded, and despite the name, was much smaller than cenote azul. The cenote is sort of horseshoe-shaped, and you can leave from several wooden platforms in the middle. There is only maybe 15 feet of open water between the platform and the opposite wall at most, but you could swim into some barely lit rooms and the area was larger. It was also much larger underwater. I could watch scuba diving parties with their underwater lights and be surprised how far away they were, discovering whole rooms that I wouldn’t have known were there. Cenote azul was like swimming in a huge well, but this was more like a flooded cave. There were stalactites hanging down into the water, sometimes just above, sometimes into the water. From the dark areas, you could look back towards the daylight and see beautiful blue and turquoise colors punctuated by shadows of stalactites and swimmer legs. Because there were more people in a smaller, shallower area, the water was not nearly as clear at Gran Cenote than at cenote azul, but the feeling of swimming around on top of a cave was unique and worthwhile. I would definitely like to come back and do some diving trips into these cenotes, because I think that that is how you see the majority of their awesomeness.

Getting ready to explore the water and caves.

A view from above.

Cheating Winter (Mexico - Part 1)

Ah, cheating winter. It feels good. There hasn’t been that much winter either in Massachusetts, Colorado, or Michigan yet this year (at least while we were in any of those places), so it’s not like we're fleeing from the frozen depths of February, but it was plenty gray and gloomy when we left Detroit on the shortest day of the year. Four hours and a few thousand gallons of jet fuel later, we touched down in Cancun, Mexico.

The Cancun airport is nice and modern, bathrooms clean, and Hertz rent-a-car was no problems. Folks were friendly and generally helpful So far so good.

First stop: fuel and food. We were so hungry that we couldn’t handle spending time finding local food, so (sadly) ended up at McDonald’s. It’s always interesting seeing the local spin on America’s export – in this case, they gave little packets of spicy jalepeno death as well as standard ketchup.  Good times.

The gas station attendant tried to hustle me – I paid 400 pesos (cash) for 390 pesos worth of gas. I was going to give him a decidedly unearned 10 peso (about $1) tip. Instead he tried to scam me, hiding one of my 200 peso notes and replacing it with a 20 peso note. He tried to demand the “rest” of the bill. Too bad for him I had just been to the ATM and knew that I only had 200s, and there was no way I had given him a 20. I just shook my head and walked away, and he didn’t push it. I should have reported him, but I didn’t know how, didn’t have any proof, and didn’t feel like spending the first several hours of my vacation dealing with police bureaucracy. No matter – locals trying to hustle gringo for an extra buck should be expected, and they weren’t going to harsh my vacation mood.

We set out down the nicely-maintained highway towards Playa del Carmen and Tulum, our destination for the evening. Two uneventful hours later, we arrived in the town of Tulum just after dark. It was loud and traffic-heavy, but there was a music festival going on and there seemed to be quite a few nice tourist shops/restaurants, without it being overwhelming or terribly Gringo-ized. We found a dive shop to purchase a mask and snorkel, which we had foolishly forgotten back in Massachusetts. It was only another 10 miles or so to our bed for the night, but it took longer than expected.

First we had an easy cruise to the hotel zone along the beach (our first beach sighting!), which ended at the border of Sian Ka’an Biosphere Reserve, a Mexican National Park and UNESCO World Heritage Site (yet another for our list). We paid our 150 pesos for 3 days admission and thought we were almost there.  Only 2.5 miles left, but what a 2.5 miles!

The dirt road had more potholes than road (our pictures just don't do it justice). Whenever I took the econo-rental car out of first gear it was a mistake. Too fast! I found myself  weaving left, right, back center, back right, trying to find a path through the craters.   Thankfully our cheap Chevy has been trustworthy thus far (hopefully it will get us down the path once more). Recent rains left some of the potholes full of rain, making them much more difficult to judge depth and likelihood of suspension-crushing peril.  

Finally, we arrived at CESiak – the Centro Ecologico Sian Ka’an, (www.cesiak.org) an eco-lodge and education center that runs tours and hosts scientific researchers. The reserve itself is the largest preserve on the Mexican Caribbean, and has lots of wildlife in the jungles, lagoons, dunes, and coast. There are 336 bird species found here, more than in all of Europe, for instance.

Our Cesiak lodging was a cabana perched on stilts above the primary dune of this peninsula (ecologically speaking, it would be better sited further from the ocean).  There is a wooden platform with thatched roof, and then a frame canvas tent is built inside, providing protection from mosquitoes, rain (mostly), and most importantly, wind. Oh man is it windy here. Inside we had a proper queen sized bed and two candle lanterns with proper hurricane lamp covers (I didn’t know that the shape of the glass had a function, but Shannon informed me of this. They work – it was so windy, even with most of the windows zipped shut that I worked thorough 6 matches trying to light them, but they stayed faithfully burning for hours after that.) There is no power or plumbing in the cabana, but there is 24 hour power (solar and wind powered, all off the grid) in the office, and composting toilets a short spider-filled walk away. (Did you know: if you hold a flashlight near your eyes and shine it toward the ground in the dark, you will often see little sparkling jewels all through the woods. These “jewels” are usually the eyes of spiders, shining back at you. Shannon does not like this at all.) Our bed had been decorated with a swan made out of our beach towels – it felt like a pretty damn classy tent!

The swan towel that welcomed us to our tent/cabin.

Even with the ocean-facing screen window mostly zipped shut, our little tent rocked and rolled in the wind all night. Occasionally, the wind would shift and the tent wall would slam into the headboard of our bed and shake us awake. Shannon eventually resorted to earplugs over the din, but I rather liked the roar of the wind and crashing surf. The real estate is hard to beat. We wouldn’t enjoy the color of the turquiose water until the next morning, but I did enjoy the dark dark sky, probably the darkest I’ve ever seen at sea level.  (Science note: There is much more humidity here than in the mountains or desert, obscuring the stars somewhat, but the removal from civilization was pretty good here. Cesiak has also kept outdoor lights to a minimum. This is mostly because of their power restrictions from being off-grid, but also aids with sea turtle conservation. When baby sea turtles hatch, they orient to the sea by finding the brightest thing around and flippering like mad across the sand to this. Naturally, the crashing surf is brighter than the forest on land. Unfortunately, human outdoor lights screw them up, leading many baby turtles to head the wrong way when they hatch. Also, for reasons I don’t fully understand, bright shore lights discourage female turtles from both coming ashore to nest or from actually laying eggs if they do come ashore).

The spray off the waves was driven into the tent a little, even through the screen, so that it was a bit damp in the tent by morning. No matter. It’s gorgeous, and it’s almost all to our selves. There are only probably 30 people staying here, plus a similar number coming for day tours. The fine sand beaches are ours to play on.

Our first day we didn’t go anywhere. We got up and had a tasty breakfast at the Cesiak restaurant, then played in the surf for a few hours. It was much too rough to use that snorkel we’d bought, but the waves were fun to jump in. Once in a while I successfully body surfed. The water is so warm (82 F or 27C, roughly, based on a satellite image I found). It is much warmer than the Red Sea was last winter (my life is so hard…). The dry air in Egypt combined with slightly cooler water meant that after snorkeling in Egypt (with a thin wet suit) I was shivering uncontrollably. Here, I could play for hours and still feel comfortable. Awesome.

The view outside our tent.

On a whim, I spent an hour or so before sunset picking up trash. I don’t think any of it was local – it had all spent many weeks or years riding the tides. Plastic never dies it seems, it just washes ashore somewhere. Mostly I picked up plastic bottle caps and bits of bottles. I wish that in the hour I fully cleaned up my little piece of paradise, but alas, the task was greater than I. Oh well. Just trying to leave things a little bit better.  Maybe I’ll try to do something good for every place we visit, to ease my travel/carbon guilt just a smidge.

Today we had a busier day. We got up early (by vacation standards) to head into Tulum to visit the Mayan ruins before the tour buses arrived. We didn’t quite beat the crowd, but it was still a great visit. It is a beautiful site, right on the coast. The town of Tulum was occupied later than the bigger/fancier places like Chichen Itza, and had Mayan inhabitants much later, even after Spanish contact. We didn’t bother taking the time or spending the money for a guide, so mostly we just wandered around and looked at 700 year old temples and oohed/aahed at the views.

See the face in the corner?

The beautiful Caribbean Sea and part of the Tulum ruins behind us.

After that we headed back down the bumpy road (take-out taco + speed bumps = lunch disaster) to Cesiak for an afternoon kayak tour in the lagoon. We spent 3 hours paddling, sometimes in very still water next to the mangroves and other times battling some stiff chop in the heavy wind in the open water. It was great for birding, but we didn’t see the expected crocodiles (I think I’m OK with that…felt a little exposed in the kayak for that kind of wildlife encounter). We paddled out to a few islets made entirely of mangroves that are used as bird nesting grounds.

An osprey nest in a mangrove.  You can see two osprey on the left.

Each islet had different birds. Birds seen: cormorants (2-3 kinds), rosy spoonbill (look kind of like flamingoes), great blue heron, egret, vireo, pelican, frigate bird, and probably more that I forgot. There were a few puffer fish by the dock, and Shannon spotted a small sting ray in the silty water. The late afternoon warm light was lovely on the mangroves, water, and birds. “Sian Ka’an” is transliterated Mayan for “Where the sky is born” and our trip on the lagoon had indeed had some great sky views. Our guide, Fernando, learned Mayan as his first language, Spanish in school, and now also guides in English, French, and Italian - talented guy.

We finished off our day by splashing in the surf again once we got back to camp, and then inhaled some tasty chicken fajitas. I tried a few dabs of habanero salsa, which was a mistake. The burn lasted quite a while. I think Shannon has already passed out cold.  

Tomorrow we’ll leave the coast and head to Chichen Itza. It will be our second consecutive pyramid for Christmas (last year we were in Cairo). It’s good to be us. 

The beach at Cesiak.  It's good to be us.