This is a banded sea krait, a very venomous sea snake found in Malaysian waters, usually near mangrove swamps.
Once, when I was scuba diving in Malaysia, we came across one of these snakes swimming and hunting. Now this snake generally avoids humans but one bite from this snake and you are toast.
All of us avoid this thing like the plague but my crazy scuba instructor swims towards the snake, catches it by the tail with his right hand, places his left hand beside his right hand and quickly moves it up towards its head while squeezing it. The snake gets all the air squeezed out of it (I’m serious, this guy was nuts), holds the sea snake like an arrow (right hand on its tail and left hand behind its head), aims it 45 degrees upwards (aka Robin Hood firing his bow pose) and then releases the snake.
The snake, upon release, zips upwards towards the surface of the water while the instructor gets everyone to quickly skeddadle out of the area. When we surfaced, I asked him what he was doing and why the snake didn’t bite him – he said that by squeezing all of the air out of the snake, the snake needed to surface immediately to get oxygen.
However, the snake would be pissed after getting its oxygen and would sometimes come back down to the sea bed to find the diver who did this to him! Suffice to say, I never dived with him again! I hope the dude is still alive after trying stunts like this.