Reeves compares the many moods of the sea to a "hungry dog." In doing so, he illustrates that the sea is angry and unpredictable. During the day, the dog "rolls on the beach all day/ With his clashing teeth and shaggy jaws" and at night, he "bounds to his feet and snuffs and sniffs/ Shaking his wet sides over the cliffs/ And howls and hollos long and loud."
Reeves ends the poem by telling us that even the "hungry dog" from above has a quiet side and can be peaceful and serene. In this way, we can compare the sea and the dog that represents the sea to humanity and its many moods.