The two pieces of evidence that show Harborough considers the sharks as belonging in the ocean are:
b. "The shark was not passive, in the element, was I was; it was monarch of the waves, it could drive through them with the precision of a torpedo."
c. "I had invaded a realm which I had no business to invade. . . and its guardian was come to punish me."
These selections indicate Harborough's recognition of the shark as a powerful, rightful inhabitant of its oceanic environment, suggesting that he feels out of place in its domain.