"The Old Man and the Sea" by Ernest Hemingway

The story is about an old Cuban fisherman and his battle against a marlin far out in the Gulf Stream. The old man’s name is Santiago and his only friend is a young boy called Manolin, who also lives in the small fishing village near Havanna, Cuba. The boy used to go fishing with the old man until his parents stopped him because Santiago was regarded as "unlucky". Having not caught a fish for the last 84 days, Santiago sets out alone one morning… He catches a fish on his hook and the fish pulls him far out to sea. The old when the fish grows weak and slows its pace Satiago says,"Man is not much besides the great birds and beasts. Still I would rather be that beast down there in the darkness of the sea. Unless sharks come. If sharks come, God pity him and me." 
By saying this the old man reveals that he is afraid of sharks.

This is a good example of an instance in literature where sharks are portrayed as vicious. Hemingway does not explicitly describe the reason Santiago fears sharks but he eludes to the fact that Sharks are fish to be afraid of more than any other creature