Spiny soft-shelled turtle (Trionyx spiniferus spiniferus)
This is a post about a turtle, but the photo here at the top is of a freshwater mussel survey. These are biologists (Shari, Mike and Diana) from the Illinois Natural History Survey literally crawling in the river shoving their hands into the muck and sand substrate of Kickapoo Creek to find freshwater mussels. Using this technique over the course of a three year study in this stream, we found quite a few freshwater mussels of about fifteen different species.
As you can imagine, this is difficult work. The water is cold. The substrates are hard. Pushing fingers into a river bottom over and over again tends to have a battering effect on the hands, and the hazards are probably too many and unpalatable to mention here. If you need any insights into the mind of a biologist, you should be aware that most of the people in our lab loved doing this job. Certainly I did.
One day in particular, that love was put to the test.
We had covered a large transect with a sand and gravel bottom. We were just about to quit and leave for the next site when I remembered that this stretch of stream also included a substantial side channel. In this channel was a spot where an massive burr oak had toppled into the stream. When it fell, it pulled up its' root ball and left a deep divot that had become permanently filled with water and created a pool.
Standing there at the edge of the side-channel, I immediately saw a small depression in the sand just inside the pool. Hmm. That could be a buried mussel, says I to myself. I strode confidently to the spot, thrust my hand into the depression and drove it down into the muck.
Normally, the feel of a buried mussel is so slick and substantial that even cold-numbed or bruised fingers can distinguish them immediately. In that side-channel pool, I did indeed feel an object buried in that small depression. My fingers closed around it reflexively. "Gotcha!" I was pleased to have found something in this unique habitat and I was curious what it might be. I noticed this specimen seemed unusually large and the texture wasn't quite what I was expecting. Never the less, with a firm steady pull, I was able to begin extracting the mystery mollusk.
Our project was especially concerned with mussel diversity. We wanted to know if the new sewage treatment plant being built on this creek was going to affect its' biodiversity. To that end, we had been tracking nutrients and fish populations and algae growth and all manner of data before and after the plant was open.
It had always been a pleasure to find animals along the creek. One day it might be a massive whitetailed deer bounding out of tall grass, antlers broad enough to form a chair with extra room on either side. The next it might be one of the beavers we found literally everywhere building dams and gnawing trees. Over time was saw innumerable songbirds, raptors, coyotes, reptiles...
...one day I had even stood amazed as a spiny soft-shelled turtled glided to a spot just beside me in a sandy riffle...and shimmied into the sand until it was completely buried and invisible. In the blink of an eye it disappeared leaving just the tip of its' snout visible above the sand. Who would have thought a simple turtle capable of such a thing?!
Those things weren't really on my mind that day in the side-channel pool. I was, however, a bit confused as to why a mussel would be so difficult to pull out of the muck. How odd so much force would be required. I remember imagining briefly how unique and interesting this mussel must be! After one final pull my hand emerged from the goo...
....with my fingers curled around a bony reptilian face complete with razor sharp lips, two eyes and a snout.
A few admissions are in order.
First, there was shouting. I must admit that for the next few seconds the air was filled with loud yelping verbage as profane as ever a terrfied biologist might ever muster. I pulled my hand away from that mouth and leapt backward with a speed and alacrity I have seldom mustered before or since.
Second, to be entirely truthful, the wildlife of Central Illinois are farily benign. It's pretty hard to play the fearless naturalist when the most ferocious thing for miles and miles around is a white-tailed deer. However. If one were determined to be injured by wildlife in a stream in Illinois, grabbing a turtle by the face might be one of the more effective ways to accomplish that. "Man mauled by turtle" would have been an attention-getting headline in the News-Gazette to be sure.
One additional admission that is necessary here is that I am not entirely sure it was a softshell turtle I had grabbed. The snout was foreshortened and covered with mud and from the angle I held it and was thus of indeterminate length. The lip seemed heavy and there were fine lines running along it toward the mouth. I did go back to the spot were the turtle was buried and found the broad back of his shell by thrusting my foot down through the muck. It was smooth and quite large but somehow I wasn't really in the mood to dig it all up. I confess I've told this story before with the species in question having been a common snapping turtle.
I can't honestly say which it was.
As you can imagine, this is difficult work. The water is cold. The substrates are hard. Pushing fingers into a river bottom over and over again tends to have a battering effect on the hands, and the hazards are probably too many and unpalatable to mention here. If you need any insights into the mind of a biologist, you should be aware that most of the people in our lab loved doing this job. Certainly I did.
One day in particular, that love was put to the test.
We had covered a large transect with a sand and gravel bottom. We were just about to quit and leave for the next site when I remembered that this stretch of stream also included a substantial side channel. In this channel was a spot where an massive burr oak had toppled into the stream. When it fell, it pulled up its' root ball and left a deep divot that had become permanently filled with water and created a pool.
Standing there at the edge of the side-channel, I immediately saw a small depression in the sand just inside the pool. Hmm. That could be a buried mussel, says I to myself. I strode confidently to the spot, thrust my hand into the depression and drove it down into the muck.
Normally, the feel of a buried mussel is so slick and substantial that even cold-numbed or bruised fingers can distinguish them immediately. In that side-channel pool, I did indeed feel an object buried in that small depression. My fingers closed around it reflexively. "Gotcha!" I was pleased to have found something in this unique habitat and I was curious what it might be. I noticed this specimen seemed unusually large and the texture wasn't quite what I was expecting. Never the less, with a firm steady pull, I was able to begin extracting the mystery mollusk.
Our project was especially concerned with mussel diversity. We wanted to know if the new sewage treatment plant being built on this creek was going to affect its' biodiversity. To that end, we had been tracking nutrients and fish populations and algae growth and all manner of data before and after the plant was open.
It had always been a pleasure to find animals along the creek. One day it might be a massive whitetailed deer bounding out of tall grass, antlers broad enough to form a chair with extra room on either side. The next it might be one of the beavers we found literally everywhere building dams and gnawing trees. Over time was saw innumerable songbirds, raptors, coyotes, reptiles...
...one day I had even stood amazed as a spiny soft-shelled turtled glided to a spot just beside me in a sandy riffle...and shimmied into the sand until it was completely buried and invisible. In the blink of an eye it disappeared leaving just the tip of its' snout visible above the sand. Who would have thought a simple turtle capable of such a thing?!
Those things weren't really on my mind that day in the side-channel pool. I was, however, a bit confused as to why a mussel would be so difficult to pull out of the muck. How odd so much force would be required. I remember imagining briefly how unique and interesting this mussel must be! After one final pull my hand emerged from the goo...
....with my fingers curled around a bony reptilian face complete with razor sharp lips, two eyes and a snout.
A few admissions are in order.
First, there was shouting. I must admit that for the next few seconds the air was filled with loud yelping verbage as profane as ever a terrfied biologist might ever muster. I pulled my hand away from that mouth and leapt backward with a speed and alacrity I have seldom mustered before or since.
Second, to be entirely truthful, the wildlife of Central Illinois are farily benign. It's pretty hard to play the fearless naturalist when the most ferocious thing for miles and miles around is a white-tailed deer. However. If one were determined to be injured by wildlife in a stream in Illinois, grabbing a turtle by the face might be one of the more effective ways to accomplish that. "Man mauled by turtle" would have been an attention-getting headline in the News-Gazette to be sure.
One additional admission that is necessary here is that I am not entirely sure it was a softshell turtle I had grabbed. The snout was foreshortened and covered with mud and from the angle I held it and was thus of indeterminate length. The lip seemed heavy and there were fine lines running along it toward the mouth. I did go back to the spot were the turtle was buried and found the broad back of his shell by thrusting my foot down through the muck. It was smooth and quite large but somehow I wasn't really in the mood to dig it all up. I confess I've told this story before with the species in question having been a common snapping turtle.
I can't honestly say which it was.
I am quite sure, however, it wasn't a mussel.
Oh. And when the study ended two years into the plant's operation, we did find some evidence that it was causing some mussels to lose weight. Fortunately, the numbers and diversity of mussels (and fish) were unaffected. Hopefully someone will be keeping an eye on that over time. I'd be willing to help...
...but I might not sample the side-channel pool.
posted by T. Brook Smith at 7:11 PM
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