Yes, snake boots would be a neccesity here. I have only lived here ( south west GA) for about 14 months and have seen 12-13 rattle snakes, 2-3 moaccasins and countless non venomous species. Even in winter months the temp doesn't drop below 60's in the day. Probably 5 out of 12- 13 rattlers were seen in Oct - Dec range. Though they were not really responsive they were out of the ground. We actually have a festival here in Jan. called the "Rattle Snake round up" I hope this was of some help to you.
Absolutely needed and necessary.
As waltor stated it doesn't get cold enough for them to completely stop moving about. Those Cottonmouths can be really aggressive and will come looking for trouble.
If you will be wading thru water or easing along swamp edges I would go a step farther and get some snake proof chaps as well and watch your hands, most snake bites are to the hand/forearm area.
What do you do with those empty nylon feed bags or dog & cat food bags? Can you say recycle? I use them for target practice for the youngsters. Take your empty shopping bags, stuff them into an empty nylon feed bag. You can also use old clothing or rags, (but put them in the bottom so it doesnt get top heavy). When your bag is full, fold the top over, punch some holes into the top and zip tie the top shut. Paint, draw, paste, or have the kids decorate their new target. Set it out 10 or 20...