Likely Pied-billed Grebe; also called Hell-diver (regional name).

This is a long dark feather with bold white crossbars and an uneven-looking base. If from a Pied-billed Grebe, it belongs to a compact, secretive waterbird with a short, stout bill, a distinctive breeding-season black bill band, and a habit of diving rather than taking flight readily.

Mostly very dark brown to black, with two conspicuous white bars or patches across the lower portion. This pattern is compatible with a grebe flight feather, but is not diagnostic by itself.

The main vane is closely knit and pennaceous. The visible edges look somewhat frayed or disrupted near the base and adjacent fragments.

A slender, dark central rachis runs nearly the feather’s full length. Dark barbs form the main vane, interrupted by sharply contrasting white sections.

Appears smooth and compact, with a slightly glossy dark surface; close inspection of barb details is limited by the photograph.

Probably from the wing, based on its elongated, asymmetric outline; a definitive primary-versus-secondary placement is not possible.

The combination of a narrow, asymmetric dark vane and two bright white bars is most notable. These markings suggest a flight feather but do not securely identify the species.

Pied-billed Grebes inhabit freshwater ponds, marshes, and slow-moving wetlands with emergent vegetation, nesting and foraging near cover.

Occurs widely across the Americas, from Canada and the United States through Central America and much of South America; many northern birds migrate south, while others are resident.

Grebes are aquatic predators that eat small fish and invertebrates, linking wetland food webs. Their presence can reflect the availability of healthy, vegetated freshwater habitat.

Other grebes and some waterbirds can have dark-and-white barred flight feathers. Identification should be checked against a feather reference using measurements, the full feather, and locality.

Pied-billed Grebes can sink gradually beneath the water by compressing their plumage, often leaving little more than the head visible. They also carry chicks on their backs.

No species-specific cultural use can be inferred from this specimen. Wild bird feathers may be legally protected; avoid selling or keeping feathers where wildlife laws prohibit it.

Photograph both sides beside a ruler and retain any matching feathers found nearby. Compare the full shape and barring with regional feather guides; do not rely on color alone.

The feather appears detached and somewhat damaged or incomplete near its base; overall condition is fair. Wear, bleaching, and molt stage cannot be assessed confidently from the image.