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Welcome to Brazos Bend State Park. That's me on the trail, some years ago.
With so many animals in Brazos Bend State Park there are many interactions between predator and prey. With luck, we get to witness some of them.  In my experience, most
visitors to BBSP think of Alligators when they think of predators there.  But we have so many others, and I would suggest we have more than one "apex" predator in the 
park--and I really enjoy pointing that out to visitors.
Besides Alligators, we have Otters, Bobcats, and Coyotes.  Rat snakes might count in that list.  In the air, we have Bald Eagles, Northern Harriers, Red-Shouldered Hawks, 
Red Tailed Hawks, Great Horned Owls, Barred Owls (to name just a few).
And, I would add Great Blue Herons to the list.  In their environment (which can be anywhere, because they can fly and then walk on all terrain with those amazing legs), they 
can kill and eat almost anything, and swallow prey of surprising size.  The GB Herons fascinate me because they are so large, yet move with such leisurely grace and control; 
only to stop, stalk, and then-with a movement that seems effortless-stab prey. If the prey is large, it is rendered helpless within a few seconds; although it can take a few
minutes more to make the prey totally inert. They are apex predators in their environment, and will eat almost anything...

Update 03/19/2024 - 03/10/2024  Brazos Bend State Park  I was watching various wading birds in Pilant Slough near the Observation Tower at 40 Acre Lake. They were
foraging on the floating plant mats.  I like to watch this behavior to see what the birds are catching. The birds move quickly, and there are many of them, so it takes some
luck for me to be watching the right bird at the right time to see a successful capture of prey.  It takes even more luck to catch it with a camera. For a long time (years?) I've
been hoping to film the capture of one specific animal--and today I was successful!  The pictures on not very good, but they are still clear enough for me to identify the
prey. The Great Blue Heron, Ardea herodias was at least 25 yards away, and I shot a burst of photos when it grabbed something.   I couldn't identify the prey until I got
home and examined the photos. The images below were taken as a single burst of photos (at 10 images per second); so the prey was gone in less than a second.
What was it?  The Great Blue Heron had caught and eaten an Eastern Newt, Notophthalmus viridescens.  I've known the newts live here. We've caught them during our
 Pond Life Programs. 
   

While growing up in the Northeast U.S., I'd found the newts many times, and had kept them briefly. I'd also found Red Efts up there, and in that environment I'd found them
nearly the size of adult newts, and VERY bright orange.  I had learned that the Eft stage was toxic, and the orange was a "warning" color (this is called "aposematic" coloration).
Here's an study:
"Chemical Defense of the Eastern Newt (Notophthalmus viridescens): Variation in Efficiency against Different Consumers and in Different Habitats" by Zachary H. Marion, Mark E. Hay.
If you'd like to read it, here's an open-source link(my favorite kind):  https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3229496/

From this study (notes in [[double brackets]] are just my own comments):

1) "Like Taricha newts, the eastern newt (Notophthalmus viridescens) is assumed to deter predators by secreting TTX, with all life-history stages reportedly unpalatable to a variety of vertebrate
and invertebrate predators. "  [[ TTX=tetrodotoxin. They are toxic at *all* stages!?!? ]]

2) "The lack of rigorous research on the chemically-mediated predator-prey interactions involving Notophthalmus viridescens is surprising given that eastern newts are thought of as keystone
predators that regulate the diversity and abundance of larval anurans, aquatic invertebrates, and the ecosystem functions of some freshwater environments." [[ *Keystone predators*!?  This little
amphibian? What a great example of how much a single organism can affect pond life. ]]

3) "The eastern newt (Notophthalmus viridescens Rafinesque, Salamandridae) is one of the most widely distributed salamanders in North America and occupies lentic environments
across the spectrum from temporary to permanent water bodies."  [[  Where I come from, I knew them as "Red-Spotted Newt", but they're the same species. ]]

4)  " Notophthalmus viridescens secrete tetrodotoxin (TTX) which could serve as a chemical defense against predators. Concentrations of TTX are greatest in the red eft stage,
followed by adults, eggs, and finally larvae."  [[ As stated above, TTX is in all stages, although greatest in the red eft stage (which has the warning colors). ]]

5) " To assess newt palatability to co-occurring consumers, we used adult largemouth bass (Micropterus salmoides; 15–20 cm standard length [SL]), juvenile bluegill sunfish (Lepomis macrochirus; 2–4 cm
SL), the crayfish Procambarus clarkii (9–12 cm total length), and adult bullfrogs (Lithobates catesbeianus; 12.5–18 cm snout-vent length)."  [[ The list of predators that they used are all inhabitants at BBSP also.
The crayfish is our big Red Swamp Crawfish. It is native here, and the same species that is cultivated and served in restaurants. ]]

6) "Here we show that eastern newts, their early ontogeny, and especially their dorsal skin areas are distasteful to common aquatic consumers such as fish and crayfish, that fish avoid newts due
 to chemical deterrents, and that the compound TTX can produce this response at small portions of its reported natural concentrations. Yet some consumers, such as bullfrogs and possibly
other reptiles and amphibians, appear undeterred by TTX." (page 6)

7) "Our results show that the newt Notophthalmus viridescens is unpalatable to fishes and a crayfish, and that this unpalatability is chemical in nature, is concentrated in exterior dorsal skin, and is
likely due to TTX or related secondary metabolites. However, this chemical defense is ineffective against bullfrogs (and possibly turtles), allowing considerable consumption of tethered newts in
the field." (page 7)

From my observation here, I can add Great Blue Herons to the list of predators that eat Newts.  The last two images below show that the Newt was swallowed (its head is
visible in image #3), and it was gone after image #4 and the images that followed (not shown here).  It does make me wonder if the TTX has any effect on the Herons
after they've eaten a newt. I have seen other wading birds catch newts but it has been a very rare observation, and I have never been able to capture it on film before.

   

Here's an Eastern Newt, Notophthalmus viridescens, that we caught at during a Pond Life Program a few weeks later, on 03/24/2024 .
   

On 01/15/2023  I was at BBSP, and it was an interesting day.  First, about 9:30am, this Great Blue Heron (Ardea herodias) caught a Lesser Siren (Siren intermedia) out of Pilant Slough near
the Spillway Trail. I've seen many GB Herons capture sirens many times. Here in BBSP my experience leads me to believe that whenever I see a GB Heron with long, thick, dark prey--I 
assume that it's caught a Lesser Siren. Sirens are  amphibians, described as salamanders that only have 2 front legs(missing the rear legs), and external gills. Some of these images show 
the Siren's short front legs.  The row of vertical grooves on the Siren's side (costal grooves) are also visible. The wet exterior, thick body, flattened tail, and the costal grooves help identify the
prey as a siren from a distance. If one is closer then the two short front legs can sometimes be seen; and a combination of these elements help distinguish it from a snake or an eel.
   

When park visitors see this, they are often surprised when the Heron swallows the siren. But many people don't realize that all the wading birds with long necks and pointed beaks are predators;
and unlike other avian predators (such as Eagles or Hawks), Herons. Egrets, Bitterns, etc. don't cut or tear their prey into smaller pieces before eating it. They swallow it whole.  The entire
process seems violent, but the Heron moves precisely and efficiently. Almost every thrust of its beak strikes its target; and after the initial capture, most stabs hit a vital point in the head,
neck, or chest. The power of some of the strikes is illustrated by the points of the beak fully penetrating the prey--even going through the skull in some cases.  While editing the video clip,
I discovered that this Heron's stabs at the Siren were very consistent, and I also tried to figure out how fast those strikes were. The video was filmed at 60 frames per second (FPS). Therefore
each frame was 1/60th of a second, or .0167seconds. I counted frames from when the Heron's head started to move, to when the neck was fully-extended. This usually took 8 frames (but I used
10 to make things even).  That gave me 1/6th of a second, or .167 seconds for the strike.  I estimated the length of the thrust to be 2 feet ( I couldn't find the length of a GB Heron's neck
anywhere).  If the beak travels 2 feet in 1/6th of a second, then it will travel 12 feet in a full second; so 12FPS.  12 fps x 60 = 720 feet per minute; 720 x 60 = 43,200 feet per hour;
43,200/5280 = 8.18 MPH.  The edited video is here (it's about 10 minutes long, and shows the other event described below).
   

About 2:30pm I was near the Observation Tower at 40-Acre Lake. About 70 yards East, a Great Blue Heron stalked across the floating growth carrying squirming prey. As mentioned above,
 my experience leads me to believe that whenever I see a GB Heron with long, thick, dark prey--I assume that it's caught a Lesser Siren. But another look through binoculars showed me I was
wrong. I moved closer, along with a group of visitors, to watch the conflict. This time, the Heron had caught a snake. And, the snake was a Cottonmouth (Agkistrodon piscivorus)!  The Heron
 displayed the snake from all angles, so I could verify the general chunky body shape, bands with irregular boundaries, black "stripes" along the sides of the head, and the shape of the head.
It was a beautiful snake! I was sorry to see it in such a predicament.
   

The group of visitors with me were amazed by the struggle. Some were surprised when I identified the Cottonmouth and verified that it was venomous. When they asked how the Heron could
successfully attack the snake without being bitten, I told them that the Heron was a predator, and an expert at handling prey. Throughout most of this event, the Heron maintained a tight grip on
the snake's head, or right behind the head.  Most of the heron's handling involved rapid rotations of the beak and head--probably trying to break the snake's neck. When a heron handled a
Siren that morning, it mostly stabbed the Siren and picked it up (by the front end). If it moved, the heron dropped the Siren and stabbed it again.
   

Handling of the snake was a bit different. There was more apparent squeezing of the head and neck, and very few "drops" at first. When the heron did finally drop the snake, it immediately
stabbed for the skull, and pierced it quickly.  This immobilized the snake, and it was swallowed soon after. The edited video is here (it's about 10 minutes long, and shows the other event
described above).
   

 About 2:50pm a heron caught another snake in the same area.  I only got a short look at it, but from the general color and shape, and the lines I could see on its belly, I think this was a
Graham's Crayfish Snake (Regina grahamii).. 
   

The Heron subdued and ate this snake very quickly.  We can compare the pictures to see the differences between the Cottonmouth and the Crayfish Snake and the Siren. The Crayfish Snake
was not as thick as the Siren or Cottonmouth, not glossy, with markings on belly. The Siren was glossy, dark, with flattened tail, costal grooves, and legs. The Cottonmouth had scales,
patterns on back and belly, back of the head much wider than the neck at that point, and differently shaped head.  This was a lot to see in one day!
   

Part 9 of 9 (for parts 1-8 go to this page) : On 12/04/2022  The water was still high. In the morning, the mother alligator was visible, but I couldn't see any of the babies at first. 
   

A larger alligator (probably the "2nd gator" that had been sharing the area all along) moved in behind the mother! At one point, it even bumped the mother alligator and one of them made a
very low, quiet, short "growl".  The mother didn't move, and the other alligator backed off and moved away. It eventually climbed onto the floating plant mat. One picture shows how close the
2nd gator was, and also shows the size difference between them. Babies started to appear after a couple hours. They seemed to be coming out of a cavity under the bank, near mom gator's
nose in the last picture.
   

The mother also moved over to the plant mat (she's at the center in the 2nd image below). More babies moved out of that hidden cavity and climbed onto the bank. They were a few feet below
the trail, well camouflaged, and near the water. Their mother was within sight of the pod. It was a situation that I've seen many times over the years. During all of those times, I've enjoyed
watching the baby alligators, and enjoying the quiet times with park visitors that came by--for hours on some days.  But today was going to be different.
   

At about 12:30, I was doing the usual "crowd control"-keeping people back from the bank so they wouldn't scare the babies; talking about the adult gators, etc. There was a small group of
visitors around me. As we talked, and pointed, a Great Blue Heron walked along the bank, coming from the short wooden bridge. It came closer to us, then walked at the edge of the trail
--only 6 feet away from us!!--then moved to the edge of the concrete culvert.  I asked everyone to be still, and watch what would happen next. The heron paced to the left edge of the culvert,
looked down the bank, stalked down the bank, and grabbed a baby alligator! Right in front of us!  
   

The images of the heron here are frames from video. Standing just 6 feet from the heron, I had a brief, amazed look of those huge wings opened in front of me. Reviewing the images later, I
 can admire the balance and physical prowess being demonstrated. The open wings provide balance and stability to offset the weight of the heron's neck, the energy of its strike and
recovery; all as it was leaning forward and down while standing on a steep bank. Imagine standing in the same spot, and reaching down to grab something with your hand without falling into
the water, and you may have some idea of why I could admire what was happened here. The heron turned, walked up the bank, took a step or two and took off with the baby.
   

It landed about 50 yards West, on the plant mats in Pilant Slough, and we could see it finish eating the hatchling.The mother responded by rushing into the water and over to the bank, but she
 hadn't  begun moving until after the heron had gotten back onto the trail, far too late to save the heron's prey. The babies had all submerged.
   

The mother climbed onto the trail near the culvert, and  rested there. She was still there when  I left.  Although I knew the heron was stalking the babies, I was still very surprised that it ignored
 me and the crowd and grabbed one. As mentioned above, I've put together an 11-minute long video that summarizes this, with the added attraction of video clips showing some of the action.
 That 11-minute video is here.
   

From Brazos Bend State Park on 11/06/2022 About 5 minutes after the snake crossed, there more drama! Great Blue Heron that had been stalking the area (baby gators were around) 
stabbed into the weeds and came up with squirming prey colored with stripes. At first I thought it had caught a baby gator...but then recognized it had caught a snake. With the apparent 
black with white speckled colors, I thought at first--Speckled King Snake. That didn't make sense (I don't think this is its favored hunting zone). I watched the events happen, and tried capturing
enough images to identify the snake.
   

Some of the images are grabs from video, too.  Let's try to identify the snake. The head is not shaped like a pit-viper's (not blunt profile, no gland swelling at the rear of the jaws).  The top
(dorsal) color is a sort of dark green. Not any bands across the body(head shape & round pupil & no mask(stripe on side of head) rule out Cottonmouth. No stripes along the dorsal and sides.
So not a Ribbon Snake or Garter Snake. Could be a water snake. No orange colors on top or bottom--so not Broadbanded Water Snake. But look at that pattern on the belly, especially
 visible starting near the tail and stopping about 4 inches behind the head. It's not a double line--so not a Crayfish Snake.  How about this: "numerous yellowish half-moons, they cover most of
the belly, which is typically yellowish-white on the forward third and grayish or brownish on the midbody and the rear". --from Texas Snakes-A Field Guide by Dixon and Werler ©2000 page198.
This sounds about right to me. If it is, then this was a Mississippi Green Water Snake (Nerodia Cyclopion)  The Heron dealt with the snake as they normally deal with large prey. There were
multiple stabbing, picking up to sense movement, drop and stab again cycles,; until it was time to swallow the snake. This was a bit of a problem, because the snake had tied the rear of its
body into a very large knot. This discourage the Heron, but only for a little while. It did finish its meal.  Interesting times in a very small part of the park.
  

From BBSP on 10/16/2022 (update added 11/14/23)   Walking along Pilant Slough Trail, I noticed the quick movement of this heron catching
something. It was a dragonfly. I've seen Great Blue Herons catch many types of prey, including dragonflies--which they usually grab when
the insect has landed. But while I was watching through the camera, the heron looked up, and grabbed another dragonfly out of the air!! 
Amazing catch! I'd intended to share the experience before, but it was put out of mind by later experience. But, here it is! The images below
are frames from this very short video.
     

From BBSP on 06/05/2022   Due to trail construction, lack of rain, and the heat, the water level in Pilant Lake has dropped dramatically over the last month or so.
The first picture, taken near the Observation Tower, shows how far the water has lowered, and the small channel made by drainage.  Through the day (and I stayed on the trails between
40Acre Lake and Elm Lake) I saw a LOT of green herons. They might have also been taking advantage of the prey being exposed by the low water.  This Great Blue Heron had caught a
Broadbanded Water Snake.  That was another uncommon sight for me. I usually see them catching Sirens, or various fish.

From BBSP on 02/06/2022. We've got Bobcats in the park, and Coyotes, and Otters, and Alligators! So what could some toothless critter do? HOLY COW!
When the day started, it was about 42 deg F at 40-Acre lake at 8:10am.  Throughout the day, I had the usual array of encounters with wonderful creatures. About 4pm I was moving
 West on the 40 Acre Lake trail when this Great Blue Heron caught a Lesser Siren just North of the trail. That's always an amazing sight and the visitors on the trail were impressed.
But then the Heron flew across the trail and landed on an island in 40 Acre Lake. The islands are about 30 yards away from the trail, so we could easily watch the end of the hunt.
I've been lucky enough to see this activity many times. For example,  just the last few times I've been able to photograph Herons capturing Sirens on 9/05/2021, 11/07/2021,
12/12/2021, 01/06/2022, and this day.  These images are all frame grabs from this edited video.  Imagine the strength in the Heron's body and neck that allowed it to carry that
struggling siren--while the Heron was flying!

   

I've seen that Great Blue Herons usually use the same technique when dealing with larger prey items.  They capture the prey by impaling it with their beak. If the Heron was wading, they move
 onto land. If the prey is still struggling, it is dropped and then impaled again. The prey is lifted, and the Heron pauses. I believe it is checking for movement.  
   

If the prey is still struggling, the process repeats as the prey gets weaker. When the prey has stopped moving, it is then swallowed--WHOLE. The entire process usually happens pretty quickly
so it is easy to miss just how formidable the Heron's beak is. The Heron's aim was usually true-striking the head and upper body of the Siren. Also, the beak easily penetrated skull, body, and
even went through the Siren and into the dirt.  Amazing power! This Heron had a little problem handling the Siren, and it took longer than usual to eat it. I would guess that this Heron is younger,
and had less hunting experience.
   

Great Blue Herons can swallow very large prey--this is one with a bowfin that I filmed in 2006.  I've got more images of GB Herons capturing prey on page 1, and other Herons here.
   

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