Peter Benchley's love of the ocean causes him to sound an elegiac note in Beast, because the ocean may be irreparably damaged unless the destructive tendencies of the human race are placed under strict control. In the novel, the North Atlantic has been overfished, and the lack of fish threatens the livelihood of many people such as Whip Darling, whose family has been fishing the waters off Bermuda for several generations.

Benchley explains that the use of fish traps by many boatmen is one of the main causes of the depletion of the ocean. Thoughtless greed has led these fishermen to destroy their own way of life. The giant squid that normally finds its food in the ocean depths now must hunt for it closer to the surface.