The title suggests a temporary camp, and the poem seems to place us at its edge, at the moment something opens. A door swings open "like a new mouth," a striking image that makes the opening feel alive, as if the place itself has started to speak or breathe. It also sounds a little hungry, which prepares for the eating that follows.
Then the focus drops to small, ordinary visitors. A couple of pigeons come near, but they find "the box too bold." The word "bold" is interesting: the box, perhaps the camp's shelter, feels like a loud presence to these wary birds. So they keep their distance and drink and eat beside it instead of at it.
The speaker never states a feeling, but the quiet, patient observation suggests calm attention and a gentle sympathy. The mood is hushed and watchful. Human space and wild creatures share a spot cautiously, each making room for the other.