Glossary of Bird Terms

The following glossary terms were developed by Gregory Gough, USGS
Patuxent Wildlife Research Center.

abdomen: ventral part of the bird. Synonym(s): belly.
alula: three feathers springing from the base of the primaries. Synonym(s): alular quills.
alular quill coverts: feathers overlying the bases of alula.
alular quills: three feathers springing from the base of the primaries.
Synonym(s): alula.
auricular: area around ear opening. Synonym(s): ear patch.
axillary: ventral area between the body and the wing. Synonym(s): wingpit.
back: dorsal part of the bird.
BBS Breeding Bird Survey: this survey is typically performed in June
by volunteers on over 4000 bird counts. The counts are done by vehicle
during the morning. Many nocturnal or less vocal species are not well surveyed by the BBS. Data from this survey is used to generate the BBS maps.
belly: ventral part of the bird. Synonym(s): abdomen.
bill: beak.
body: main mass of the bird as distinguished from its appendages.
breast: front part of the chest.
breast band: stripe across the breast.
breast spot: small, differently colored area on the breast.
cap: top of the crown.
CBC: Christmas Bird Count. This survey is performed in one calendar day any time from mid-December to early January by volunteers. Birds are counted in an area with a 15 mile radius. Data from this survey is used to generate the CBC maps.
cere: fleshy area between the beak and face.
cheek: Area bounded by lore, eye, auricular, and lower mandible.
chest: front part of the body.
chin: part of the face below the bill.
collar: rear portion of crown. Synonym(s): nape, hindneck.
comb: colored area over eye found in males.
commissure: base of the bill where the mandibles join. Synonym(s):
gape, rictus.
crest: tuft on the head.
crissum: Feathers covering underside of base of tail. Synonym(s): undertail coverts.
crown: Top of the head.
culmen: Upper ridge on bill.
dihedral: Wings of a flying bird held at an angle appearing to form a "V".
ear patch: Area around ear opening. Synonym(s): auricular.
ears: Rounded, earlike areas on the face. Synonym(s): facial discs.
eye: Organ of sight.
eye line: Line of feathers in front of and behind the eye.
eye ring: Pale-colored feathers encircling the eye.
eyebrow: Line of feathers above the eye. Synonym(s): supercilium, superciliary line.
eyelid: Skin-fold covering the eye.
face: Front part of the head.
facial discs: Rounded, earlike areas on the face. Synonym(s): ears.
feet: Terminal part of the leg.
flank: Area between the belly and the wings, more posterior.
flank stripe: Band on the flanks.
flight feathers: Primaries and secondaries.
forehead: Part of the face above the eyes.
foreneck: Front part of the neck. Synonym(s): throat, jugulum, throat
patch.
frontal shield: Extension of the bill onto the forehead.
gape: Base of the bill where the mandibles join. Synonym(s): commissure, rictus.
gonys: Lowermost ridge on lower mandible.
greater secondary coverts: Feathers overlying bases of secondaries.
gular region: Between the chin and the foreneck.
head: Upper part of the body.
head stripes: Bold lines on the head.
hindhead: Rear portion of crown. Synonym(s): occiput.
hindneck: Back of the neck. Synonym(s): nape, collar.
horns: Paired contour feathers arising from head.
inner primaries: Group of primaries closest to the body.
inner secondaries: Group of secondaries closest to the body.
inner wing: Shoulder, secondaries and secondary coverts.
iris: Colored part of eye.
jugulum: Front part of the neck. Synonym(s): foreneck, throat, throat
patch.
knee: Joint in the middle part of the leg.
leading edge of wing: Front edge of the wing in flight.
leg: Limb used for supporting the bird.
lesser secondary coverts: Feathers overlying bases of median secondary coverts. Synonym(s): marginal coverts, shoulder.
lore: Area between the eye and the bill.
lower mandible: Lower part of the bill.
lower mandibular tomia: Cutting edges of lower mandible.
malar streak: Area at the sides of the chin. Synonym(s): whisker, moustache.
mandibular ramus: Prong-like, posterior projection from bill.
mantle: Upper surface of the wings and the back.
marginal coverts: Feathers overlying bases of median secondary coverts. Synonym(s): lesser secondary coverts, shoulder.
median line: Stripe through the crown.
median secondary coverts: Feathers overlying bases of greater second-
ary coverts.
moustache: Area at the sides of the chin. Synonym(s): whisker, malar
streak.
mouth: Cavity bounded by the bill.
nape: Back of the neck. Synonym(s): hindneck, collar.
nasal canthus: Anterior corner of eye.
nasal fossa: Depression in which nostril is located.
neck: Part connecting the head to the main part of the body.
neck patch: Inflatable sac on neck used by males in courtship display.
nictitating membrane: Translucent, vertical fold under the eye lid.
nostril: External naris.
occiput: Rear portion of crown. Synonym(s): hindhead.
operculum: Swollen structure in pigeons overarching the nostril.
outer primaries: Group of primaries farthest from the body.
outer secondaries: Group of secondaries farthest from the body.
outer tail feathers: Part of the tail farthest from the center.
outer wing: Alula and primaries.
passerine: Of or relating to birds of the order Passeriformes, which
includes perching birds and songbirds such as the jays, blackbirds, finches, warblers, and sparrows.
patagial mark: Dark patch on leading edge of underside of inner wing.
pelagic: Living on the open ocean rather than coastal or inland bodies of
water.
pileum: Top of the head extending from the base of the bill to the nape
pinnae: Projecting feathers.
plumes: Large, conspicuous, showy, feathers.
primaries: Flight feathers attached to the "hand".
primary coverts: Feathers protecting and covering the primaries.
primary numbering: System for assigning a number to each primary.
pupil: Contractile aperture in iris.
rectrices: Conspicuous feathers forming posterior margin of tail.
remiges: See primaries and secondaries.
rictal bristles: Stiffened feathers near bill.
rictus: Base of the bill where the mandibles join. Synonym(s): gape,
commissure.
ruffs: Fringe of feathers growing on the neck.
rump: Area between the uppertail coverts and the back.
scapulars: Area of feathers between the back and the wings.
secondaries: Flight feathers attached to the "elbow".
secondary coverts: Feathers protecting and covering the secondaries.
shoulder: Feathers overlying bases of median secondary coverts.
Synonym(s): lesser secondary coverts, marginal coverts.
side: Area between the belly and the wing.
side of neck: Area of neck between foreneck and hindneck.
spectacle: Eye ring and supraloral line together.
speculum: Highly colored area on secondaries of several ducks.
suborbital ring: Eyelids.
subterminal band: Stripe before tip of tail.
superciliary line: Line of feathers above the eye. Synonym(s): super-
cilium, eyebrow.
supercilium: Line of feathers above the eye. Synonym(s): eyebrow, superciliary line.
supraloral line: Line of feathers above the lore.
tail: Feathers extending from the rear of the bird.
tail coverts: Under and uppertail coverts.
tail numbering: System for assigning a number to each tail feather.
tarsus: Part of the leg between the knee and the foot.
temporal canthus: Posterior corner of eye.
terminal band: Stripe at tip of tail.
tertiaries: Feathers adjoining the secondaries.
throat: Front part of the neck. Synonym(s): foreneck, jugulum, throat
patch.
throat patch: Front part of the neck. Synonym(s): foreneck, throat,
jugulum.
tibia: Part of the leg above the knee.
toe: Digit attached to the feet.
trailing edge of wing: Rear edge of the wing in flight.
underparts: Belly, undertail coverts, chest, flanks, and foreneck.
undertail coverts: Feathers covering underside of base of tail.
Synonym(s): crissum.
underwing: Underside of wing.
upper mandible: Upper part of the bill.
upper mandibular tomia: Cutting edges of upper mandible.
upperparts: Back, rump, hindneck, wings, and crown.
uppertail coverts: Feathers covering upperside of base of tail.
upperwing: Upperside of wing.
whisker: Area at the sides of the chin. Synonym(s): moustache, malar
streak.
wing: Moveable feathered appendage.
wing bars: Pale tips of greater and median secondary coverts.
wing coverts: Primary and secondary coverts.
wing lining: Median, lesser and marginal coverts on underwing.
wing stripe: Paler area at base of flight feathers.
wingpit: Ventral area between the body and the wing. Synonym(s):
axillary.
wrist: Area at base of the primaries.

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