I've killed a few of those in my yard.Still I don't fear them.
P.S. They are tasty if you cook them the right way.
Rattlesnakes scare me, that rattling they do before they bite you. But the cotton mouths scare me the most, boy do they make you sick and we have them all over. My earliest childhood memories are of going fishing down close to Grande Isle Louisiana and being in a boat going down little like bayous with water mocassins up in the trees hanging out over the boat. Every once in a while, one would drop and we were instructed if it happened not to move or jump out of the boat while my dad dispatched him. I also remember Dad pushing the boat out into the water and pulling it back on the bank and lifting us up into it, just in case there were snakes under the boat. Damn, I hated those infernal fishing trips. I just hated them.