Here are my other Brazos Bend
and/or critter pages:
---------------------------------------------------------------- OR, FOR OTHER ANIMALS:
Alligators at Brazos Bend State Park Introduction Critters at Brazos Bend State Park Page 1
Snakes-nonvenomous 1------------------------------------------- Critters at Brazos Bend State Park Page 3
Snakes-nonvenomous 2-------------------------------------------------Insects, non-toxic
Snakes-Texas Rat Snakes------------------------------------------------
That's me on a trail (03/29/2004). As I get more pictures, these pages expand. I've gotten enough images of snakes to collect them here. For most of my identification, I'm using "Texas Snakes-a field guide", by James R. Dixon and John E. Werler (2000, 2005)
Sunday is usually busy at Brazos Bend State Park. So, I usually bring
my bicycle to allow me to cover more of the trails. Today I rode about
repeating loops over the Elm Lake, Spillway, Pilant Slough, Live Oak, and 40 Acre Lake trails. I was riding West on the Spillway Trail when a couple of park visitors called my
attention to a Barred Owl in a tree above the trail. Further description is on my Owl Page.
Soon after, I noticed some park visitors looking at something at the edge of the trail about 20 paces East. When I went there, I saw a beautiful Broadbanded Water Snake
in a high periscope position. I explained that the snake was raising its head above the ground cover to see what what around it, and that it probably intended to cross the trail. The snake
lowered itself into the cover, and appeared again next to the trail as a shorter periscope. And then...it crossed. This video shows the snake moving across the trail. Notice how the markings
on the snakes face cross the jawline, and the orange, black, red and brown coloration. These markings clearly identify this snake and differentiate it from any of the 3 venomous snakes
that might be encountered at the park.
03/27/2016 I was riding my bicycle towards Elm Lake when I passed a snake on the trail. When it didn't move as I rode by, I assumed that it might be dead or wounded--perhaps
run over by a bicycle earlier. So I turned around and went back to the snake. It was a nice speciman of a Broadbanded Water Snake (one of our prettiest snakes). Water snakes in
general do not take kindly to being handled, and will often strike at hands put near them. So, I was careful as I approached the snake. I gently prodded it with a small twig, and it
moved, and flicked its tongue. So, I decided to try to pick it up. I just slid my hand under it, and lifted it on my palm. The snake rested there until it seemed to warm up, and began
moving around. So I released it. It was a bit cool this morning, but I didn't think it was chilly enough to cause the snake to be torpid. I any case, it moved off into the grass.
It was cold this morning-about 42° F when I got to the park-but sunny.
As the day progressed, it did start to warm. At about 11 am, I heard
the soft call of a frog
in distress, and I looked for it. I knew that I have a relatively short time to find the frog (and usually, the snake that has it) before the frog is gone. I got lucky
and found the snake. It was hidden in the grass, but I was able to find the snake. It was well hidden by the grass, and I stayed back enough to avoid disturbing the snake
(this was about 8 feet away). Through manipulation of the camera, and some luck, I was able to get focussed on the snake, and filmed what I could through a small gap in the
cover. Images below are frame grabs from the video clips. I have edited the clips together and the result can be seen here. This is probably another Gulf Coast Ribbon Snake.
Ribbon Snakes are non-venomous, and are not constrictors. Therefore, they have no way to quickly immobilize their prey-so they have to struggle with it once it's been caught.
They seem to snag frogs by a back leg--probably because the frog leaps as the snake strikes. The snake's hooklike teeth take hold, and then it works the jaws and teeth to work
the prey into its mouth (or to work the snake over the prey). It can still happen fairly quickly, unless the frog is large, relative to the snake's head. Then it can be an extended
tug-of-war, but the snake seems to usually be successful. I have not found any information on why the frog makes the sound when it has been seized. Perhaps it's trying to
get the attention of a larger predator--which could eat the snake.
I was suprised to see a snake moving around in such cool weather--especially one that was hunting! The ground where the snake was hidden was tilted towards the sun
and had been getting warmer, but the air temperature was still probably around 50° F. In the book How Snakes Work by Harvey B. Lillywhite, it says that snakes generally
"prefer" a body temperature of 29° - 34° C (page 109). That's 84.2° - 93.2° F; and quite a bit warmer than it was this morning. In the same book, it refers to a behavior
called "acclimatization" in reptiles. This is a tendency for the "preferred body temperature" to shift (within limits) if the average environmental temperature has changed
to a higher or lower range for a period of time (i.e. seasonally). This means that the snake make actually be able to function properly at lower temperatures than normal due
to changes in body chemistry. In the case here, we had just experienced a cold front which had dropped the temperature at least 20 degrees, but it was a relatively short-term
event. Within a few days, temperature had returned to 60's-70's. BUT...we are in the fall season, so the snakes may acclimatize regardless.
Here's what I what I was wearing that day, because it was cold (below left).
And near Noon, smaller alligators (generally 3 - 6 feet) came out of the water, like this 5-footer. This is discussed in Biology and Evolution of Crocodylians, by Grigg and
Kirshner. I'm still working my way through the section on thermoregulation, but I can see that it is not a simple matter for alligators. Many factors influence whether or not
a particular alligator will come out of the water to bask. In fact, the connection between basking and thermoregulation is not clear--especially for larger animals.
Above some size, body mass allows the crocodilian to maintain a very stable "thermal inertia"--which means that the internal temperature changes very little over the course
of 24 hours. Generally, smaller animals (say less than 5' long) warm faster (and can't hold their breath as long either, but that's another issue) and cool faster than larger
animals. Depth of the water is probably a factor, too--deeper water isn't going to cool as fast as shallower water. So, along the section of trail where I was, the average
water depth may be about 4', and the smaller gators came out to try to warm themselves. Not many did, but I didn't see any larger ones come out of the water at all in that area;
although a showed their heads at the surface.
12/14/2014 Not Snakes and Ladders-Snakes and 'Gators!! On this Sunday, I spent a few hours by the mother alligator and her babies.
Clouds began covering the sky about 12, so I packed up my scope and moved to 40 Acre Lake. Near the South end of the East part of the trail, an alligator was up on the bank. I stayed near it for
a while, to talk to any park visitors that came by. I saw a group of people moving towards me, so I moved to the side of the trail across from the alligator. While I was
moving off the trail, I looked down at the leaves...and noticed black scales glistening in the shadows. I carefully brushed some of the leaves away, and revealed a beautiful
Since the snake was just off the trail, and directly across from the alligator, I stood very close to it, so noone who was avoiding the alligator would step on the snake.
Although they were interested in the alligator, but when I pointed out the snake hidden the grass near me (it was about 3 feet long) they decided it was time to move on.
When the group left, I decided I'd better move the snake a litte further off the trail, so no one would step on it. I gently picked it up, and used the opportunity to take some
pictures of it. The snake was very calm an cooperative. The shiny, "black" scales at the top, and the bright red underside are easy identifiers for the Mud Snake.
After a few pictures, I placed it closer to the Pilant Slough overflow, and moved back a few steps to give it space.
When I stopped, I looked back and down and noticed-curled up a couple feet from the water-another snake.This one was a Cottonmouth. It didn't move while I watched it, and I took some
pictures of the Cottonmouth. Then the Mud Snake started to move, so I took a step closer to that. While I was watching the Mud Snake, I heard the peep/splash of a frog hitting the water.
When I looked that way, I saw the Cottonmouth slowly moving towards the water and moving under the leaf cover. Soon, I was alone with the alligator again, so I moved on down the trail.
NOTE: I know the heading of this page is "non-venomous 4", and the Cottonmouth is venomous. But, it was next to the Mud Snake, so I left the stories together.
With the weather cooling that afternoon, I was probably watching two methods of snakes thermoregulating. In the book "How Snakes Work" by Harvey B. Lillywhite, there are examples of different
methods used by snakes to keep their Preferred Body Temperature (PBT) at the correct level. Many snakes have a PBT of about 29-34 degrees C (page 109). This is 84.2 - 93.2 degrees F. Sometimes a
snake can use leaves as insulation. (p. 107) It appeared that the Mud Snake was using the leaves. Meanwhile, the Cottonmouth was still lying on top of the leaves, trying to get direct solar
Also interesting is that the preferred body temperature of a snake can vary with the season. That is, if the average daily temperature changes to a different constant, then the snake's PTB could shift with it;
so that its body will work most efficiently at the "new" temperature. These changes are produced by the snake altering its chemistry (by adjusting the levels of various enzymes). Also, these changes are
reversable! This is called "acclimatization" when it happens in the wild, or "acclimation" when inducedin a laboratory. (p. 110)
Gaining or losing heat by movement and use of external heat sources is called "Behavioral Thermoregulation". (p.105)
Why do snakes thermoregulate? According to the book, (p.113) 2 main reasons are:
1) to avoid extreme temperatures that would threaten their lives. For instance, to avoid getting so cold that they cannot move enough to avoid freezing.
2) to help their bodies function at peak efficiency. For example, for proper digestion, or for coordinated nerve/muscle function during hunting.
About 10 minutes later, I saw this Gulf Coast Rbbon Snake (Thamnophis proximus orarius) foraging near the trail. As it moved through the undergrowth, it lifted its head straight up--a behavior I call "periscoping".--to see its surroundings. Sometimes, I just get lucky. Two different snakes in 10 minutes!
8/21/2011--I was walking on the West side of the Elm Lake Trail when I noticed that high, long "chirp" that may mean that a frog is being attacked. I moved slowly and carefully towards the sound, and finally saw movement in some grass. By using the high zoom on my camera, I was able to get a few pictures of a snake just finishing the act of eating a frog. One has to be quick when locating the frog making the sound, because the struggle sometimes ends quickly. I think the snake is a Gulf Coast Ribbon snake (Thamnophis proximus orarius). The 3 scales at the tip of the snout appear to be tan-colored, and there are two yellow scales (2 spots) at the center of the top of the head. The frog is probably a Southern Leopard Frog (Rana Sphenocephalia), but I only saw part of its head.
11/14/2010--At about 8:45 AM, I was walking on the West end of the Spillway trail when I noticed this Western Mud Snake (Farancia abacura reinwardti) next to the trail. The air was a bit cool (I was dressed in warm clothes) so the snake was quite sluggish. I carefully picked it up and was happy to see that it was alive and unharmed. As I held it, it coiled into a ball, possibly for defense. I took some pictures, but couldn't get a good look at its tail. I've got more information, and pictures of a young Mud Snake, on one of my other web pages (look for the date March 29, 2006). After I took my pictures, I placed the snake back in the grass along the trail.
a small bird. It was a small frog! A Green Tree Frog (hyla cinerea),
and it had been caught by a Ribbon Snake (thamnophis proximus).
It was really difficult to see amongst the leaves, and the tree swaying
in the gusts of wind didn't help. I finally found the snake with the viewfinder
of my camera, and snapped one picture. Then, I set up the video camera,
found the snake with that, and left it on the tripod to film while I tried
to take some more still images. Unfortunately, with the teleconverter and
the movement, I had a really hard time finding the snake again, and only
shot one more still image.
I did get more with the video camera, though.
PECULIAR FRUIT BETTER CLOSEUP VIEW EATING WITHOUT LIMBS COMPLETED MEAL
get more with the video camera, though. The first two images above (PECULIAR,
CLOSEUP) are from the first still image, cropped and resized. I've read
in many places that snakes usually eat their prey headfirst, to allow for
easier folding of the limbs as it is swallowed. This frog is going in rear
legs first. Consider the amazing feat of catching and eating this meal---without
any limbs! The snake had to climb the tree, stalk the frog and then catch
it. Then, with the frog still very much alive, the snake has to manipulate
the frog down its throat AND STILL HOLD ONTO THE TREE--all without the
aid of any limbs. The snake used a combination of specialized muscles and
scales to climb the tree and hold itself in place. The frog is trapped,
and manipulated by extremely sharp teeth. Each of these teeth are curves
so their points are towards the snake's throat. Moving away from the throat
causes the points to dig in, and the teeth to hold. The only way to easily
get free of the teeth is to move down the throat. The process is helped
by the snake's full control over the actual shape of its jaws. Each side
can move independently to work alternatively to pull in, or to grab. The
third image above (WITHOUT LIMBS) is a frame from a short clip (
SNAKE w FROG WMV 3173MB)
that shows some of this action. The clip is edited from much longer footage
to remove the swaying of the tree and to shorten the clip. I've also cropped
it from the full-frame clip. The last image above (COMPLETED MEAL) shows
the snake resting after its meal. It's the only other picture I was
able to take.
I've heard the occasional cry of a frog being eaten, and sometimes I've found the frog in the clutches of a snake---sometimes I never find it. I wonder why frogs make this sound. It's unique, and once heard, is not easily forgotten. It just sometimes blends in with the various other cries and calls from birds and insects, so I don't notice it. Is this a reflex? Is the intent to call attention to the frog, and the snake, so a predator may appear and attack the snake? Is it to warn other frogs? I understand they are not social, but this kind of programming would serve to minimize damage of the frogs in a particular location by a hunting snake.
Brazos Bend State Park The main page.
Bend State Park Volunteer's Page The
volunteer's main page.
Go back to my home page, Welcome
Go back to the RICKUBISCAM page.
Go back to the See the World page.