The discussion between Whitney and Rainsford has many elements of foreshadowing because what Rainsford learns about and experiences on the island afterwards not only help to develop the theme, but also the philosophy behind hunter vs. "huntees." First of all, the island's name is Ship-Trap Island. Titles and names represent the nature or character behind them. General Zaroff gets all of his game from sailors who either fall off their ships, like Rainsford does, or who have been shipwrecked and set adrift.
Next, Rainsford and Whitney discuss hunting, which is only a game to hunters, especially General Zaroff, but life or death to the prey. Whitney brings up this perspective because Rainsford will soon experience what it is to be prey when he falls victim to General Zaroff and his island game. The foreshadowing to these events can be seen in the following discourse:
"'The best sport in the world,' agreed Rainsford. 'For the hunter,' amended Whitney. 'Not for the jaguar.'"
Then, when Whitney discusses omens of the sea, or the possible truth behind sailors' feelings, which he warns Rainsford not to disregard. He gives Rainsford the following example:
"There was no breeze. The sea was as flat as a plate-glass window. We were drawing near the island then. What I felt was a--a mental chill, a sort of sudden dread."
The absence of breeze suggests lifelessness and doom. Mental chills are like omens that warn one about what is to come in the future. For instance, Rainsford is about to sense sudden dread for his own life when he becomes Zaroff's prey.
Finally, falling into line with every foreshadowing hint as set forth in this discussion, Rainsford falls overboard when he strains to see the island in the dark when he hears the report of a gun. The text describes Rainsford's fall into the ocean like a foreshadowing for the events to follow, as in this sentence:
"The cry was pinched off short as the blood-warm waters of the Caribbean Sea closed over his head."
The words "blood" and "water" both represent life or death, depending on the circumstances around which they are used. In Rainsford's case, he faces death once he falls into the ocean and winds up on Ship-Trap Island.
From the beginning of the story, there are three foreshadows of what will take place.
First, right from the beginning we learn that the island is a foreboding place. When Rainsford asks his friend, Whitney, about the place, Witney says that the locals call is Ship-Trap Island. This speaks of the danger of the place.
Second, as Whitney and Rainsford are talking, the topic is hunting. Whitney says that he believes animal fear. Rainsford dismisses this. Instead, he says that the world is made of two types - hunters and huntees. Little does Rainsford know that he will be hunted. Here is the dialogue:
"Nonsense," laughed Rainsford. "This hot weather is making you soft, Whitney. Be a realist. The world is made up of two classes--the hunters and the huntees. Luckily, you and I are hunters. Do you think we've passed that island yet?"
Finally, as Rainsford is swimming to shore, he hears two shots. Someone is hunting; the implication is that he hears Zaroff hunting. Soon, Rainsford will become the object of Zaroff's hunt.