Snake ID: Venomous?

[robotspacebrain]

Saw these two snakes near a natural spring pool in Austin, TX.

Any ideas?

[infernalis]

harmless water snake

[FWK]

harmless water snake

Yep. Look like Green Water Snakes.

[robotspacebrain]

Thank you for the help. Could I ask what you use to make the identification?

[millertime89]

Just a couple of fat and happy nerodia (non-venomous water snakes).

[guidofatherof5]

Nice looking water snakes. Non-venomous but many love to bite and bite repeatedly.:D

[IW17]

Thank you for the help. Could I ask what you use to make the identification?

One way to tell is that the pupils are round. This isn't fool proof with all venomous snakes but in venomous water snakes, aka the cottonmouth, the pupils are slits, like a cats eye.

[FWK]

Thank you for the help. Could I ask what you use to make the identification?

It's like anything else, if you are very familiar with the snakes even very small differences become very obvious. IW17 is right on with the eyes, Cottonmouths are pit vipers and have "cat eyes" were as Water Snakes have round pupils. But there is no need to get that close, if you look at pictures of a Cottonmouth and Water Snake side by side you'll notice their heads shapes are very different. It's bit harder when you see a snake in the wild and have nothing to compare it to but that is were experience comes into play. There are other differences as well but the shape and size of the head relative to the rest of the body is a dead giveaway and easily identifiable at a glance with a little practice.