As the title suggests, the speaker of "Crusoe in England" is the castaway Robinson Crusoe, from Daniel Defoe's famous 1719 novel of the same title. In other words, this poem is a dramatic monologue: it's spoken in the voice of a character who is not the poet. It's also a very loose adaptation of its source material: Bishop changes Crusoe's character, setting, and story in many key respects. The poem's opening lines start to establish her Crusoe: the original spin she will bring to this classic tale.

The title also makes clear that Crusoe is narrating this poem from back home "in England." In other words, he's no longer trapped on a desert island. He's re-immersed in civilization, even plugged in to the media landscape. In fact, he begins by mentioning some news he's recently read in "the papers." This news turns out to relate to his former island—which, in Bishop's version of the story, was volcanic.

First, Crusoe reports that "A new volcano has erupted" somewhere in the world. Then, he recounts that "last week I was reading / where some ship saw an island being born." Evidently, this island was "born" from a separate, undersea volcanic eruption. (Islands formed in this way are known as high islands or volcanic islands.) Crusoe describes what the ship's crew witnessed: "first a breath of steam, ten miles away," followed by the appearance of a "black fleck," likely made of the volcanic rock called "basalt." (Basalt forms from cooling and hardening lava.) This fleck looked as small as a "fly" through the "binoculars" of the ship's "mate" (second-in-command) and seemed to catch "on the horizon" as if sticking to flypaper.

This striking imagery—including the vivid "fly" simile—immediately puts Crusoe's whole adventure into a broad perspective. As someone who lived on a volcanic island for many years, it's natural that Crusoe should follow news about volcanoes and islands. But what these "new" events seem to signify, on a symbolic level, is that the world has moved on from his ordeal. The metaphorical birth of the volcanic island is like the birth of a younger generation: a reminder of time's passage.

Moreover, the new island looks as puny as a fly from just ten miles' distance. This perspective suggests that Crusoe's great adventure—the whole drama he lived out on his island—might also be puny and trivial in the grander scheme of things. And the same might be true of anyone's solitary struggle, or anyone's whole existence. (Notice how the word "born" sets up an implied analogy between an island and an individual life.)

Before diving into his own tale, then, Crusoe seems to suggest that it's not really all that special. Islands come and go—and so do human struggles like his. On the geological timescale of the earth, these events are as ordinary and minuscule as the birth and death of flies.