Yellow-lipped Sea Krait (Laticauda colubrina)

Yellow lipped sea krait

Yellow-lipped Sea Krait  is a species of sea snake found in tropical Indo-Pacific oceanic waters. The colubrine sea krait, banded sea krait or yellow-lipped sea krait (Laticauda colubrina) is a species of sea snake found in tropical Indo-Pacificoceanic waters.Banded sea kraits are often seen in large numbers in the company of hunting parties of giant trevally (Caranx ignobilis) and goatfish. Their cooperative hunting technique is similar to that of the moray eel, with the kraits flushing out prey from narrow crevices and holes. Kraits need to drink fresh water and regularly come onto land for that purpose. These snakes can be distinguished by their yellow markings on their snout and the black bands  throughout their belly. 

This video is zoomed as the snake is not approachable

ref: http://en.wikipedia.org/wiki/Laticauda_colubrina