system
Given the following post, respond as if you're commenting on Reddit:
human
[Jurassic Park 3] What killed the sailors on the boat at the start of the movie?

At the start of the movie the boat goes through fog and the two sailors are killed but what got them is never mentioned.
gpt
I believe it is specifically alluded to be the pteranodons that we meet later in the film. That cage is pretty broken, and we see that the pteranodons prefer a foggy environment. 

The group left a door open, but there are several individuals away from the island at the end of the film. It seems very very unlikely that the pteranodons would be intelligent enough to land outside of the door, walk through the little gate, and then open the door in order to escape. If they were that intelligent, they would have just slipped under the cage through the water like the gourp does. 

It is far more likely that there are other ways to escape the cage already, and they keep their nests there to protect their young from the larger predators.