Feathers

Pennaceous

Feathers with many barbs with hooklets.

Plumulaceous feathers

Soft, loose, fluffy feathers for thermal insulation in birds. Downy feathers

Vaned/Plumulaceous feathers

Both vaned and plumulaceous. Contour feathers.

Wing feathers

Remiges

Tail feathers

Rectrices

Remiges + Rectrices

The flight feathers of a bird

Airfoil

Any surface, such as a wing, which provides aerodynamic force when it interacts with a moving stream of air.

Primaries

The outer (distal) remiges that attach to the bones of the hand and the second digit. Pennaceous

Secondaries

The inner (proximal) flight feathers of the wing that attach to the trailing bone of the forearm, or ulna. Mostly pennaceous

Contour feathers

Make up the coverts, and the body + head + neck feathers. Feathers have pennaceous ends with plumulaceous closer to the body. Pennaceous ends good for aerodynamism/waterproofing, plumulaceous closer to the body good for keeping warm.

Down feathers

Completely plumulaceous. Underneath the contour feathers. High number of feathers on the body itself. Keep the body warm.

Body down feathers

Only grown by adults. Grown from follicles that ONLY grow body down feathers. Lightweight and warming.

Natal down feathers

Grown temporarily by nestling birds in a nest. All over body and wings. Grown from the same follicles that will eventually grow the contour feathers.

Powder down feathers

"Pulviplumes" Grown by specific groups of adults (doves, chickens, herons, parrots). Feathers are located throughout the contour feathers or found within distinct patches. Feathers are so fine and frail that they can get grinded into dust (human allergen). Continuous growth. Waterproofing function.

Semiplume feathers

Transition stage between contour feathers and down feathers. Consist of rigid rachis (contour feature) and wispier barbs with no/few hooklets (down feature). very slight vane or none-existing vane. Found on the edges of contour feather tracts.

Bristles

Whisker-like feathers that are grown by birds who eat and catch insects. A form of sensory feathers usually grown around the mouth but could also be grown around the head or as eyelashes (Hornbills). Consist of the rachis and calamus (without barbs).

Filoplumes

Grown on primary feathers for feather proprioception (feeling of how the body is oriented in space). Dead structures made out of keratin. Attached to the nerve endings in skin → movement sends communication signals to nervous system.

Preening

Process in which a bird rubs oil from an oil gland over its feathers to condition and slightly waterproof them. Also reestablishes hooklet connections and removes dirt, old oil, and parasites.

Uropygial gland

Oil-secreting gland situated at the base of the tail in most birds.

Fledgling plumage

Juvenals will leave the nest with this plumage.

Formative plumage

Plumage resulting when a juvenal sheds all of its juvenal feathers but keeps its wings and tail feathers.

Basic plumage

Plumage a bird will have outside of its breeding season. Also referred to as its "winter clothes" or "nonbreeding clothes". This plumage is most of the year.

Alternate plumage

The plumage that results from a partial molt of the basic plumage before breeding. "Breeding clothes".

Definitive plumage

Final plumage, adult plumage