Formally “The Birds” is a short story. It falls squarely in the horror genre. Du Maurier uses a far-fetched event to inspire terror and dread in the reader.
Within horror, “The Birds” is considered gothic. The gothic as a literary aesthetic and sensibility is very broad, encompassing works from Bram Stoker’s Dracula to Toni Morrison’s Beloved (though the latter was not written in the Gothic literary period, even if it draws on gothic elements). Fear of the environment is a major motif in gothic literature and features heavily in “The Birds.” The protagonist, Nat Hocken, navigates a hostile, haunted landscape, where the familiar suddenly becomes strange. Not only is the natural landscape evoked in great detail via descriptions of the sea, sky, and fields, but the primary antagonist in the story is nature itself in the form of the birds.
“The Birds” is also categorized as a thriller, a genre characterized by mounting suspense and surprise. Director Alfred Hitchcock defined the genre with his films—among them his adaptation of “The Birds.” While “The Birds” is less purely psychological than many of du Maurier or Hitchcock’s other works (the birds are a tangible, external threat), the story still focuses on the protagonist’s perspective. The readers follow Nat’s thoughts and associations, his inner turmoil, and his mounting dread. It is through his perspective that readers experience fear and try to understand and predict what will happen. The speculative “what if?” of the story becomes real and frightening; readers are desperate to know what will unfold, as if, like Nat, their lives depend on the outcome.