What are examples of foreshadowing in Life of Pi chapter 46?

Foreshadowing is a technique used throughout Yann Martel's Life of Pi and in Chapter 46, foreshadowing is used to show the dangers the protagonist finds himself in and hint at what might happen to him later.
Foreshadowing as a literary device is used by the writer to give some clues about what is to come later in the story, helping the reader to start knowing (or thinking they know) what to expect. As such, it builds suspense and creates atmosphere. It can be done through dialogue or imagery, and it encourages the reader to start making connections about what might happen next or later in the text.
The narrator, Pi, gives a hint of the troubles to come by describing his difficult second night at sea as "different from later ones in that I still had the strength to appreciate fully what I felt". We know immediately then that there will be further nights, and he will start to get weaker than he currently is.
He describes how Orange Juice, the orangutan, looks at him and "expressed nothing about it. I was just another animal that had lost everything and was vowed to death." The idea of possible death is introduced, and the assumption that this could be Pi's fate. Later in the chapter, Pi shares his realization that "it was not only the day that died and the poor zebra, but my family as well."
The violence of the death of the zebra, attacked and eaten alive by the hyena, could be seen as foreshadowing the possibility of more death and attacks, including, perhaps, that of Pi himself.
When the sharks gather round, Pi states "I was not afraid we would capsize—I thought the sharks would actually punch through the metal hull and sink us." This serves to introduce the very idea of the possibility of capsizing and sinking that the reader may well now carry with them as they continue reading.
Another example of foreshadowing or suggestion is achieved with "A single fly buzzed about, sounding to me like an alarm bell of insanity." It introduces the idea of insanity and questions whether or not the narrator can be seen as reliable.