The caption is difficult for me to follow. The video seems to be a sea krait trying to eat an eel. The sea krait is an amphibious snake which is a member of the subfamily Laticaudinae. These snakes are viviparous, meaning they return to land to lay their eggs, unlike true sea snakes. This species is venomous, scientist say their venom is ten times more deadly than a rattlesnake. Note the paddle-shaped tail which makes it a great swimmer.