In Life of Pi, how is Richard Parker a factor in Pi's survival at sea?
Richard Parker as a tiger gives Pi the motivation to continue living and becomes his companion on the small lifeboat. Stranded in the middle of the ocean, both Richard Parker the tiger and Pi are forced to rely on one another for survival. Pi discovers a sense of duty to Richard Parker, which forces him to get up each morning and attempt to feed the famished tiger. Despite the obvious dangers of being trapped on a small boat with a tiger, Pi develops a mutual respect and close relationship with Richard Parker. Pi describes how Richard Parker motivates him to survive by saying,
If I still had the will to live, it was thanks to Richard Parker. He kept me from thinking too much about my family and my tragic circumstances. He pushed me to go on living. I hated him for it, yet at the same time I was grateful. I am grateful. It's the plain truth: without Richard Parker, I wouldn't be alive today to tell you my story (Martel, 81).
Pi fears being on the lifeboat by himself, which makes Richard Parker's presence invaluable.
There are also various interpretations of what Richard Parker allegorically represents throughout the novel, and each representation influences Pi's survival differently. Richard Parker as an allegorical representation of God offers Pi motivation to survive through the fear of dying and hope of discovering the truth through religion. Pi wrestles with spiritual matters, which symbolically represents his complex relationship with Richard Parker. Richard Parker as an allegorical extension of Pi represents his primal instincts to survive despite the dire situation. As a human, Pi's inherent impulses drive him to survive.
In part the answer to this question depends on whether you see Richard Parker as a real tiger or as a figment of Pi's imagination, but let's start with Richard Parker the tiger. Richard Parker helped Pi to survive by, essentially, giving him both a reason to and the will to live. Neither one of them could survive at sea without the other. Not only did Richard Parker help Pi stay alive (for example, by killing the Frenchman), but taking care of Richard Parker (by helping him eat) meant that Pi had a reason to wake up in the morning that meant more than going through the motions of surviving by himself.
On the other hand, Richard Parker remained a carnivorous animal through and through. In other words, Pi was always in danger from him. Every time he had to fight off Richard Parker or escape to avoid being eaten, it reminded him that he wanted to live. That gave him the strength and willpower to live through his ordeal.
Taking Richard Parker as an allegory (in Pi's "real story," where Richard Parker is a metaphor for himself and the other animals are the other passengers on the raft), he can be seen to represent the war of faith that Pi goes through. He prays to the Christian, Islamic, and Hindu gods to help keep him alive, relying on them for support, but he also has serious doubts about religion and sometimes clashes against it like he's fighting the tiger. In this version of the narrative, Richard Parker also becomes an allegory for the power of story itself; by making up a companion, even an adverserial one, Pi keeps himself going. Either way, Richard Parker becomes the main thing that keeps his heart and mind going.
As a figment of his imagination, Richard Parker represents Pi. At the beginning of the story, we learn of Pi’s unorthodox religious beliefs. Pi subscribes to Hindu, Christian, and Islamic teachings, to the chagrin of the local religious leaders. According to Pi, each of the three religions answered some of his questions, and he could not denounce any of them.
When he was stranded at sea, Pi prayed and hoped for a miraculous intervention to deliver him from the calamity. However, he questions God’s role in his predicament. Richard Parker/Pi questions God and his own beliefs, and his resolve to know the truth forces him to fight for survival.
As a real tiger, Richard Parker helps Pi stay alive by forcing him to rise about the situation and apply the lessons he learned from his father. Pi is forced to feed Richard Parker, and the ensuing bond grows into a sense of responsibility for the tiger. Thus, in fending off the tiger, Pi lives for himself.