We pulled over and I got out while everyone else stayed in the car. I walked down the creek and first spotted a small ribbon snake in the creek which quickly took off into the brush. As I approached what I saw, I started to get excited. I peered over the edge of a small rock cliff and confirmed that it was infact 2 Water Moccasins. I went back and got my camera as well as informed the rest of my family. We all took our time getting down to the area so as to not disturb the snakes. I filmed about 6 clips of these two male Water Moccasins fighting. At first I wasn't sure is they were courting or mating, or actually fighting. I later learned they were fighting over mating rights to a female that was likely in the area. I have lost all but one of the clips when a hard drive crashed. I was using a kit canon lens, I believe my 28-125mm. I shot this hand held with no tripod. I wish I could visit the spot again in the future but I have several issues. First I probably couldn't find the spot again even if I tried. I am not familiar with the Austin area at all.
During the 10 minutes or so that I filmed and photographed these reptiles, not once did they notice my presence. I was as close as 3 feet during some of the filming and they were too busy fighting to notice me. This has been one of my favorite things to film. It's not often you get to witness this behavior for yourself. I have seen less than a dozen Water Moccasins in the wild. I have caught hundreds of water snakes but very few are Water Moccasins. Unfortunately to most people every water snake is a Water Moccasin. They don't care to properly identify the snake and often it is killed for no reason except some naive person believes it is poisonous.
Water Moccasins are thick bodied and stubby. Usually dark brown with darker stripes that are usually uneven. They have cat eyed pupils as all pit vipers have. When harassed they will coil up and open their mouths which is pure white. This is where the name Cottonmouth comes from.
The Blotched Water Snake and the Diamond Back Water Snake are often confused with Water Moccasins.
Here is a video I took of a Blotched Water Snake.
I don't have any videos of a Diamondback Water Snake, but here are a few photographs. Notice in the first photograph of a Diamondback Water Snake the pattern is very different from a Water Moccasin.
In the photograph below you can see the Diamondback Water Snake has eaten something.
The eyes are round and not cat shaped.