More than likely those were water snakes which are insanely curious. If the body is submerged, it’s a water snake, if the body is floating on TOP of the water, it’s a cotton mouth or water moccasin.
Dark thick body, swimming on top of the water with the head a few inches above the water, triangular head, two fangs and a white mouth, curious and aggressive. I grew up around the swamp. Those were water moccasins.
I can get along with rattlesnakes but water moccasins are not your friend. When you are in a pirogue (a small dugout canoe) they can easily come over the side as you have just a few inches of free board. When you see one coming you do not hit it with the paddle as it might really piss them off. You put the paddle in the water in a position that the snake will swim over it. When he does you pull the paddle as hard as you can in an arc. It will throw the snake many yards away. At this point he is really pissed off but does not come back.
I loved the swamp when I was a kid. It was a kid's paradise but you need to know what you are doing. You can get hurt and worse if you are not careful.
1. Do not swim where there are alligators.
2. If you accidentally come across an alligator nest get the hell away quick. Mama gators are not nice.
3. Look out for water moccasins.
4. Know where the hell you are.
5. Tell someone where you are going.
6. Do not drink the water.
7. Bring Bug Spray, a lot.
8. Alcohol is not your friend until you are back at camp.
9. How do you get back if your motor fails on your boat?