Because it often swims through the water with only its neck and head visible, many people think it is a snake.
Anhingas use their long bill, which has serrated edges, to stab fish underwater. It then surfaces and flips the prey into the air to swallow it.
These birds can stay submerged for relatively long periods of time because their feathers become waterlogged. They lack oil glands that ducks and other waterfowl use to waterproof their feathers.
After swimming, the birds perch on tree branches with their wings spread out to dry. If the bird tries to fly with wet feathers, it is very clumsy and takes a good bit of effort to take off.
FOG sez: It takes a good bit of effort to get me off of the couch.