In the darkness, Asrul Tuanakota, 37, initially mistook the huge fleshy blob for a stranded boat, according to the Jakarta Globe.
Fishermen in the island’s Iha village are convinced the remains are those of a giant squid while others who have viewed the footage say the stinking mass could also be a decomposing humpback whale.
The bloated 15 metre corpse is believed to have been dead for at least three days by the time it was found.
Close up vision shows its discoloured skin turning the waters a disconcerting red as it disintegrates.
Locals have asked the government to help them remove the remains as the stench is getting worse by the day.
A group of marine scientists have reportedly taken samples of the creature in a bid to identify it.