The poem begins with the owl's call, "who who," and turns it into a question humans can't answer: who is responsible for what's been lost? The speaker doesn't name a culprit. The wordplay on "who" and "which" makes us feel the question hanging in the air, unanswered, and perhaps unanswerable because the blame is shared by everyone.
Then comes the blunt news that the owl is "dead and buried." Calling it "snappish" gives the bird a little personality, almost affection, which makes its loss feel more personal. The last lines turn sharply. People once warded off witches and spirits with noise, but now the noise is "the noise of profit," the racket of industry and commerce. The title suggests the spotted owl's habitat is at stake, though the poem never spells that out.
The speaker sounds quietly bitter and ironic, more weary than angry. The mood is bleak and hushed, like a place where the night calls have stopped and only human noise is left.