Expert: Meryl Green - 7/27/2009

Question
QUESTION: I got a picture of a snake crawling outside. It's been staying in my pond.  Can you tell me what kind it is?

ANSWER: Since that's not a particularly distinct color pattern (i.e. a lot of snakes have it) I'll be better able to help you if you can give me a general idea of where you live, something like 'central Florida' or 'eastern Mississippi' will do.  You might also like to try looking it up on enature.com; this link (http://enature.com/fieldguides/search_advanced.asp?curGroupID=7) will take you to the advanced search for reptiles and amphibians.

---------- FOLLOW-UP ----------

QUESTION: I'm sorry about not telling you where I live. I thought about that after I sent the question. I live in Southern Louisiana. Just 50 miles south west of New Orleans. Thanks again.

Answer
That's ok.  I have people all the time wanting me to identify snakes (both online and in person) from a statement like 'it was black' or 'it was huge' :P.

I think you might have a northern diamondback water snake, Nerodia rhombifer rhombifer.  That species is not venomous, though apparently it can be aggressive.  

Here are some pictures to compare your snake to.  They do vary a bit in color.
http://i.pbase.com/u18/nezmo/large/43010068.IMG_2343_edited1.jpg
http://www.herpjournal.com/2007/04_28_07/fullsize/04_28_07_1.jpg

And a good informational page:
http://www.nearctica.com/herps/snakes/colubrid/Nrhomb.htm