Lucky the shark didn't mistake the kayak for its mate and become incensed and jealous of the hapless human on her back.
Sharks don't have mates. Sharks just eat. It was trying do decide if the kayak was edible or not. No one has ever seen a shark mate, I don't think. It happens very deep underwater. They are very mysterious. Did you notice the dude in the snorkelers boat call it a very large "animal?" I've noticed them calling them "animals" lately, I suppose to try to get us thinking of them as just another animal with "rights" instead of as a killing machine.