Avian (Bird) Anatomy – Images of Feathers & Skin by Jeannine Miesle

Main Article: Avian Medical Terms / Health & Diseases by Jeannine Miesle, MA, Allied Member, Association of Avian Veterinarians …

Avian Anatomy Image Gallery (NOTE: Some of the images / illustrations on this and linked pages may be too graphic for young audiences. We recommend parental supervision and approval.)


http://www.bing.com/images/search?q=feather+tracts+in+birds&view=detailv2&&&id=938C721BF3E8CF3AD68F3F78F47 AFA657C5D3EC8&selectedIndex=0&ccid=1%2fSY7eP%2b&simid=608039426881686875&thid=JN.NwoXUpGclwD6iVP 1LMt77g&ajaxhist=0

Feather Tracts

Wing AnatomyPrimary and secondary feathering, feather numbering of wing

Bird feathers http://www.earthlife.net/birds/images/anatomy/wing.gif

Numbering of Wing and Tail feathers https://nusavifauna.files.wordpress.com/2012/08/bird_anatomy_1.jpeg

Bird Wing Anatomy

Leading edge of wingLeading edge of wing http://www.bing.com/images/search?q=leading+edge+of+bird+wing&view=detailv2&&&id=A04C6A6D17F24925EF2456B 211673B6D55097953&selectedIndex=149&ccid=DvCZsmAL&simid=608021164690639938&thid=JN.fwDqwXUM5Yjwv% 2f1tqk5kpg&ajaxhist=0

Inner wing feathers http://www.bing.com/images/search?q=inner+wing+of+bird&view=detailv2&&&id=0FD8F69BAAB720282CD2A720FABA5 67 9CBF4A077C0&selectedIndex=13&ccid=FmkYx6xG&simid=608005019906083412&thid=JN.jBWBLxcPRox7QiumBHI0V g&ajaxhist=0

Inner Wing Feathers

Wing feathers http://www.bing.com/images/search?q=bird+wing+feathers&view=detailv2&&&id=56E04B780B39624579A0450C417056 A2ECD277D6&selectedIndex=1&ccid=bFNrLqrW&simid=608027461098997025&thid=JN.ElzuSQDr7G%2faSRg6vDksH A&ajaxhist=0

Wing Feathers

Brood patch http://www.bing.com/images/search?q=brood+patch&view=detailv2&&&id=9216B471633D5A8D9BA7D618C4 24B4E1A4BFFB07&selectedIndex=13&ccid=un7L9bao&simid=608015834619776290&thid=JN.6rL5KMAnJgI3 CDrFvr%2b6QQ&ajaxhist=0

Brood Patch

Blood Feathers and feather sheaths. Blood feather and feather sheath http://www.bing.com/images/search?q=blood+feather&view=detailv2&&qpvt=blood+feather&id=A6D4730BD3C2500F8C9 C989B50D6E7D27C37FF5F&selectedIndex=5&ccid=C48qBHE/&simid=608044821348289044&thid=JN.u1jHpa

Blood Feathers and feather sheaths. Blood feather and feather sheath

Recursive Crest http://www.bing.com/images/search?q=bird+crest&view=detailv2&&&id=F727ED95B26BB7654CF57DF76D1E 68 DCC98091F1BD&selectedIndex=163&ccid=Vl1q/Gf+&simid=608031330837335601&thid=HN.6080313308373 3

Recursive Crest


Recumbent CrestRecumbent Crest http://www.bing.com/images/search?q=bird+glottis&view=detailv2&&&id=19F36453DEA8572015FDD0ED95C 7EAEC41AE09CD&selectedIndex=0&ccid=ogpWS2Ug&simid=608004298336109970&thid=JN.DAtJUsry08c% 2fjgBQEtA7%2fw&ajaxhist=0

Feather anatomy from Drs. Foster and Smith

Parts of the feather:

  • Calamus: Central shaft at the base which extends under the skin into the feather follicle.
  • Rachis (scapus or quill) feather shaft above the calamus that holds the barbs.
  • Vane: part of the feather that holds the barbs
  • Barbs: filaments on either side of rachis, extend at approximately 45 degree angle from rachis
  • Barbules and barbettes (hooklets): microscopic filaments that attach to each other, forming a tight, smooth surface. Bird keeps them attached during preening.
  • After-feathers (hypopenae): small tuft of feather at the base of the rachis.
  • Downy Barbs: barbs that are not hooked together at base of rachis.
  • Pennaceous feathers: those with barbules and hooklets, as in quill pen.
  • Plumaceous: down feathers, without rachis and quill
  • Distal Umbilicus: the base of the vane
  • Proximal or inferior umbilicus: the end of the calamus that is attached to the follicle
  • Pterylae: feather tracts
  • Apteria: featherless areas between the pterylae

Types of Feathers

Flight FeatherTypes of feathers: each type has a different function

Contour feathers:

  • Cover most of the surface of the bird, providing a smooth appearance. 69  Protect the bird from sun, wind, rain, and injury.
  • Brightly colored and have different color patterns. 
  • Divided into flight feathers and those that cover the body.

Flight feathers: Wing and tail feathers

Remiges: flight feathers of the wing, separated into three groups:

  • Primaries: long feathers attached to the manus (metacarpal [wrist] and phalangeal [finger] bones) at the far end of the wing Responsible for forward thrust. There are usually 10 primaries, numbered from the inside out.
  • Secondaries: attached to the ulna, a bone in the middle of the wing, Supply “lift” and are used in courtship displays. There are usually 10-14 secondaries, numbered from the outside in.
  • Tertiaries: flight feathers closest to the body; attached to the humorus (long bone)

Retrices: tail feathers; act as brakes and a rudder, Control the orientation of the flight. Most birds have 12 tail feathers, numbered from the center out

Coverts: Smaller feathers that cover the bases of the flight feathers There are several layers of contour coverts on the wing and ear.

FiloplumesDown feathers

  • Small, soft, fluffy, and are found under the contour feathers.
  • Plumaceous, and have many non-interlocking barbs, 
  • Lacking the barbules and hooklets seen in contour and flight feathers.
  • This makes it possible for them to trap air in an insulating layer next to the skin, protecting the bird from heat and cold. Powder down feathers: give off powder
  • When the sheaths or barbs of these feathers disintegrate, they form a fine keratin powder, which the bird can spread over its feathers as a water-proofing agent.
  • The powder assists in cleaning as the bird preens.
  • The absence of powder down in birds such as cockatoos and African greys can be a sign of disease, including Psittacine Beak and Feather Disease.


  • Fine, hair-like feathers with a long shaft, and only a few barbs at their tips.
  • Located along all the pyterlae.
  • Although their function is not well understood, they are thought to have a sensory function, possibly adjusting the position of the flight feathers in response to air pressure.

Semiplumes and Bristle FeathersSemiplumes:

  • Provide form, aerodynamics, and insulation.
  • Play a role in courtship displays.
  • Have a large rachis, but loose (plumaceous) vanes.
  • They may occur along with contour feathers or in separate pterylae.

Bristle feathers:

  • Have a stiff rachis with only a few barbs at the base.
  • Usually found on the head (around the eyelids, nares, and mouth).
  • Have both a sensory and protective function. 

Feather growth

Follicles: specialized areas in the skin where feathers develop.

Blood feather:

  • A developing feather that has an artery and vein that extend up through the shaft and nourish the feather.
  • Has a larger quill (calamus) than a mature feather  Is covered with a waxy keratin sheath that protects it while it grows
  • The sheath is removed by the bird when the feather is mature, after the blood supply recedes

Shaft color:

  • Will be purple while blood is still nourishing the feather.
  • Will change to white when blood recedes back into the body after the feather has grown out.


  • A bird will molt out or lose all of its feathers about once a year.
  • It takes months to lose and replace feathers, allowing the bird to continue to fly
  • The adult bird will gradually replace all of its feathers during a molt  This is so the bird can continue to fly and maintain body temperature
  • A molt usually takes place after breeding season.
  • reeding season is triggered by the longer photoperiod in the spring, so molting occurs during the summer; wild birds develop brighter plumage

Erector and depressor muscles in skin http://pubs.sciepub.com/materials/1/2/2/figs

Erector and depressor muscles in skin

Feather duster disease http://www.bing.com/images/search?q=feather+duster+disease&view=detailv2&&&id=3DFA1B549B49DFCC6FE3C08012 5DB9BA26BDA726&selectedIndex=0&ccid=CvNnRnV%2b&simid=608033869188628558&thid=JN.Xbn6YFGaXLHaxsTG F9CRNg&ajaxhist=0

Feather duster disease

Feather Cyst http://www.bing.com/images/search?q=bird+glottis&view=detailv2&&&id=19F36453DE A8572015FDD0ED95C7EAEC41AE09CD&selectedIndex=0&ccid=ogpWS2Ug&simid=608004298336109970& thid=JN.DAtJUsry08c%2fjgBQEtA7%2fw&ajaxhist=0 

Feather Cyst


Cross section of a bird’s skin http://people.eku.edu/ritchisong/avian_integument.htm

Cross section of a bird’s skin

Dermatitis (Miesle)