My biggest issue with this movie was that it felt like Sarah had more going on with Nick than with Ian. There was no chemistry whatsoever. I think it would have made more sense if she was his sister or something.
That was a bit obvious, as Ian did not seem to be someone who would be attracted to someone who was intelligent yet obvioulsy not smart in the slightest sense of the word. He should have told her 'Fine, stay, get eaten' and taken his daughter and the neuro toxin gun and a radio to the beach. At least he could have swum out far enough the predators would not try to come after him and his kid. And yes, sharks are a possibility, but comparing the tiny fraction of a chance of shark attack to the almost 100% chance of a predator eating you, l will take my chances in the water. All but Ian and Tembo were completely idiotic people who all deserved to be attacked by the animals.