How does general zaroff come to a realization through their experiences with animals?

The only realization Zaroff comes to is that he is bored with hunting animals. All animals were quickly hunted down by him. Zaroff wanted a challenge. He wanted to hunt an animal that could reason. THat would have to be a human. So, Zaroff started trapping ships and hunting the people from those ships on his island.

There is no evidence that Zaroff "trapped ships."

It's called Ship Trap Island because Zaroff needs men to hunt, so he literally causes ships to break up. He has installed lights to make it look as if a channel exists. In reality, the channel isn't there, but jagged rocks are that can tear a ship up, disabling it or causing it to sink. When a ship is forced to go to Zaroff's island, he has the sailors to pick from to hunt. As Zaroff says, however, the sailors don't usually provide much of a challenge for Zaroff, especially since he cheats. This is why he's so excited to get someone like Rainsford who is an expert hunter himself.

The above explanation can be found at http://www.enotes.com/most-dangerous-game/q-and-a/why-island-called-ship-trap-island-7005