Is this proof that mermaids really do exist?

IS this dramatic video proof that mermaids really DO exist?

The clip shows two tourists filming what they think is a seal on rocks.
But as they zoom in they quickly realise it might not be what it seems, with one saying: "That’s a weird looking seal man, are you filming this? I don't think it’s a seal."
The creature then appears to turn and look at the men before flipping into the water.
The clip, filmed in Kiryat Yam, Israel, has become an internet sensation with many people claiming it is a mermaid - a creature with the upper body of a female human and the tail of a fish.
So ... mermaid, seal or camera tricks? Decide for yourself.