My wife found this floating (dead) in the skimmer of our pool today. I wasn’t sure what kind of snake it was and took a picture of it. I’m wondering if it’s poisonous or not.
This is the second snake I’ve found in the pool…the first was alive and a neighbor identified it as a water moccosin.
We’re in New Orleans, Louisiana and I know there are plenty of snakes that are common around here, but we don’t see many in the suburbs, so I have no idea what it is.
Thanks,
Jason
Looks like maybe a diamondback water snake. Not completely sure, since my herping skills aren’t what my botanical skills are. 
But it’s not venomous. The head is the wrong shape.
Could be. Poisonous snakes have a triangular head (not round) and have slits for pupils (again not round). Some young poisonous snakes, however, may have roundish pupils. Certainly looks similar to a water moccasin (cottonmouth): http://www.pitt.edu/~mcs2/herp/snake.pics/cottonmouth.jpg. However, neither the head or pupil is right.
I concur that it’s a Diamondback Water Snake ( a species frequently misidentified as poisonous ). It’s the only one in that range that works. One possible confirmation ( if you still have the carcass ) is to look on it’s chin - if it was a male it will have a bunch of little bumps ( papillae) scattered there.
While not a bad rule of thumb it is worth noting this is not 100% consistent, even in the U.S., or for that matter even in Louisiana. Witness the Eastern Coral Snake.
Also vertically ellptical pupils ( “cat’s eyes” ) are seen in a few non-( or at least only mildly and rear-fanged ) venomous snakes in the U.S., like the Desert Night Snake ( rear-fanged and slightly venomous ) or the Glossy Snake ( slightly elliptical eyes, non-venomous ).
Actually, I take that back. Looking at the latter half of the body, I think I’m going to switch to the Blotched Water Snake, which also works.
