But far from being frightened, the pair appear completely unperturbed, even swimming after them in the shallow water.
One of the dogs then suddenly ducks below the surface and attacks.
"The dog is biting the shark," exclaimed the cameraman in disbelief as the pair thrashed around underwater.
"The dog is underwater with the shark. What the hell? That is unbelievable. I've seen it all now. I can't believe I've got that on film."