I’m pleased to introduce my guest blogger today, Jack Johnson, park archeologist for the Amistad National Recreation Area near Del Rio, Texas.
Thanks for joining us today Jack. I’ll bet you run into snakes frequently as you hike the area around Lake Amistad, either in the course of your work or recreationally. Ever see any rattlesnakes?
Weirdly, most of my rattlesnake stories involve trying to capture and relocate snakes that have placed themselves in the path to a restroom or latrine, and in one case done so repeatedly over several days.
Well, I’m glad that’s your job, not mine. What’s your favorite story about a snake?
Well, those rattlers were not especially big ones, nobody came close to being bitten, and this will not be that story. The snake that features in my most memorable herpetological happenstance was small, non-venomous, and was not a threat to anybody. In fact, it couldn’t hurt a bug.
One day I was leading a hike in Seminole Canyon State Park, down the dry canyon in the direction of its eventual confluence with the Rio Grande. We had passed Fate Bell shelter, the impressively large and pictograph-adorned rockshelter visited by the park’s daily tours. We were on our way to a major side-canyon called Presa Canyon, on an all-day trek that allows park visitors to explore the otherwise off-limits canyon bottoms and to experience more of the striking landscape and ancient rock art of the Lower Pecos Canyonlands. We walked over smoothly sculpted bedrock, and past two of the small permanent springs that would have provided Fate Bell shelter’s nomadic inhabitants with fresh drinking water for thousands of years. These canyon floors also have many other bedrock pools that are not spring fed, but because they are shaded part of the day by high canyon walls they can hold water for weeks after seasonal rains. The pools are an oasis in this semi-arid land and magnets for wildlife. They are home to countless insect larvae, tadpoles, and other aquatic critters and are frequented by deer, raccoons, birds, and just about every other animal out here.
Folks on tours often ask me about snakes, and inquisitors generally fall into two very different groups. The first group asks with trepidation, and if I told them there was a good chance that they would see a rattler during their visit to the park, I think some of them would go straight back to their RVs and drive until they thought it was safe to step outside again. The second group asks eagerly, and often these are snake hunters — either herpetology students or collectors or people in the pet trade — and we have to keep an eye on them as they often try to poach snakes from the park.
I tell the tour that here in the canyon bottoms they are most likely to see ribbon snakes, small and harmless relatives of garter snakes. These are pretty little snakes, almost black with bright orange and yellow stripes running from head to tail. The ones I see are usually about the diameter of a pencil and maybe 18 inches long. They live in and around the pools, where they eat the tadpoles and such. I tell people that if they think they are afraid of snakes, it goes the other way too and they should just see the urgency with which a ribbon snake tries to be anywhere else when beset by two-dozen enthralled elementary school kids on a field-trip. I tell them that if we approach each pool quietly, we may get to see one, and possibly frogs and other critters.
I had just finished so introducing the ribbon when we came around a corner and saw some commotion in the next pool down the canyon. A small snake was writhing furiously, locked in combat with something. I assumed that a ribbon snake had caught a frog or something that had more fight in it than the snake had bargained for. I was reminded of that cartoon of the frog with its hands around the neck of the water bird that is trying to eat it, with the caption “Don’t give up!” I’d never actually seen a ribbon snake feeding before, so I got out my camera and tried to think what David Attenborough would say.
As we got closer to the pool it became clear that the ribbon snake was not the predator here but the prey. A diving beetle, perhaps an inch and a half long, had a firm grip behind the unfortunate snake’s head with its pincers. Whenever the snake struggled to free itself, the beetle’s legs would unfurl and it would ride out the thrashing like a bull-rider, eventually wrestling the snake into submission. The beetle’s legs then folded back against its body, and it once more looked exactly like a floating brown leaf instead of the terrifying and thankfully small creature that it is. I had seen pictures before of diving beetles grasping little minnows, but this snake was nearly a foot long! Also, still
photos of a diving beetle nibbling on an already dead minnow did nothing to capture the violence of the life and death struggle going on in the pool before us.
Diving beetles grasp and stab their prey with huge, hollow piercing pincers that they also use to suck out their prey’s juices. When diving, they carry a supply of air with them under their wing covers, like scuba tanks. They can fly. I thought of Starship Troopers, and was very, VERY glad that diving beetles don’t get big enough to be a threat to people. I would never go near the water again! No thanks, I’ll stick with predators that aren’t so terrifying. Like big gosh-darned rattlers.
Thanks for telling us this fascinating story, Jack. And, uh, watch where you step.