Several years ago, while fishing a oxbow lake off the Arkansas river I witnessed this while fishing on Holla Bend wildlife refuge's lodge lake.

It was getting close to time to "reel'm up" the gate closed at 9:00 PM I believe and darkness was approaching. I was headed back to the launch ramp,,via trolling motor power, when I noticed a strange sight in the water some 100 yards ahead, it appeared to be a catfish,,with only his head and tail in the water,,but traveling along at a good pace considering the wake,,I hit high on trolling moter to close the distance for a better view. When I got closer, I saw that a large,,very large, water snake had a catfish of maybe 2 pounds clamped in his jaws, this was a little blue or "white" catfish and as many of you know, he had a very large belly, the snake had him by the belly and was swimming with him towards shore..I stayed back to witness the event. He went ashore in a very shallow area and attempted to go on land in several places,,but the catfish would hang in various stiff weeds along the shore, finally,,in water only a couple of inches deep, the snake coiled around the catfish and began to move his grip from the belly to the head, unhooking first one jaw,,then the other and moving towards the head..I stayed to witness this..he eventually got to the head and began to swallow the catfish, I was in awe as he swallowed more and more of the catfish,,the catfish's dorsil fin,,the tall rigid one on his back was erect, I assumed that that would be the place the snake would never get past..but when the snake got to that point,,the catfish layed down the spine,,time was running out and I had to leave,,but was there by daylight the next morning,,expecting to find both dead, no sign of either the next morning and I have to assume that the snake managed to swallow his meal..