Bill Types

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Bill Types

• Length Characteristics
• Shape Characteristics
• Color

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Long the bill is decidedly longer than the head,
as in a Ruby-throated Hummingbird or an American
Woodcock
Length
3
Short the bill is decidedly shorter than the
head, as in a Carolina Chickadee or a Tufted
Titmouse
Length
4
Comparison of Greater Lesser Yellowlegs
Comparison of Hairy Downy Woodpeckers
Length
5
Straight the line along which the mandibles
close is in line with the axis of the head, as in
a Great Blue Heron
Shape
6
Hooked the upper mandible is longer than the
lower, and its tip is bent over the tip of the
lower, as in a hawk or a parrot
Red-tailed Hawk
Hawk-headed Parrot
Shape
7
Depressed the bill is wider than high, as in a
duck
Greater Scaup
American Wigeon
Shape
8
Spatulate, or spoon-shaped the bill is much
widened, or depressed, towards its tip, as in a
Northern Shoveler or a Roseate Spoonbill
Shape
9
Gibbous the bill has a pronounced hump, as in a
Black Scoter
Shape
10
Compressed the bill, for a good part of its
length, is higher than wide, as in a puffin or a
kingfisher
Belted Kingfisher
Atlantic Puffin
Shape
11
Recurved the bill curves upward, as in a godwit
or an American Avocet
Marbled Godwit
American Avocet
Shape
12
Decurved the bill curves downward, as in a
Long-billed Curlew, a Western Sandpiper, or a
Brown Creeper
Long-billed Curlew
Western Sandpiper
Brown Creeper
Shape
13
Chisel-like the tip of the bill is beveled, as
in woodpeckers
Red-cockaded Woodpecker
Yellow- bellied Sapsucker
Shape
14
Terete the bill is generally circular either in
cross-section, or when viewed anteriorly, as in a
hummingbird
Rufous Hummingbird
Shape
15
Crossed the tips of the mandibles cross each
other, as in a crossbill
Red Crossbill
Shape
16
Bent the bill is deflected at an angle (usually
deflected downward at the middle), as in a
flamingo
Greater Flamingo
Shape
17
Stout the bill is conspicuously high and wide,
as in a grouse or a partridge
Gray Partridge
Ruffed Grouse
Shape
18
Swollen the sides of the mandibles are convex,
as in a tanager
Scarlet Tanager
Shape
19
Conical the bill has the shape of a cone, as in
sparrows or finches
White-throated Sparrow
Purple Finch
Shape
20
Acute the bill tapers to a sharp point, as in
warblers
Golden-winged Warbler
Blackburnian Warbler
Shape
21
with Angulated Commissure the commissure forms a
sharp angle at the point where the tomium proper
meets the rictus, as in the Cardinal family
Northern Cardinal
Rose-breasted Grosbeak
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with Gular Sac the chin, gular region, and
jugulum are distended, as in a
pelican
Brown Pelican
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White-crowned Sparrow
White-throated Sparrow
Field Sparrow
American Tree Sparrow
Color
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CorvidaeJays, Crows, and allies

• medium to the largest passerines
• bristles pointing forward over the nares
• bold, noisy, and gregarious
• often nest predators
• intelligent cache food

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ParidaeChickadees and Titmice

• small, sociable, and energetic birds
• short, stout bill
• cache food
• in winter, form mixed-species flocks

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SittidaeNuthatches and allies

• small, stocky forest birds
• climb tree trunks forage by gleaning
• only birds that move down trunk head first
• bill thin and pointed, typically straight
• tail short and square

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TroglodytidaeWrens

• small to medium-sized, chunky, active birds
• slender bill, often decurved
• tail usually short
• several species often have tail upright and
  cocked
• often found in shrubby habitat

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TroglodytidaeWrens

• mostly small (to medium-sized) brown birds
• almost always solitary
• active secretive creep through vegetation
• often found in shrubby habitat
• forage for insects fruit
• narrow head long slender bill, often decurved
• tail usually short
• several species raise tail above back
• most nest in cavities a few build globular nests
  of sticks grass
• aggressive towards predators, at least vocally

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SturnidaeStarlings

• medium-sized, stocky birds
• short, square tail
• gregarious
• some are mimics
• represented in NA by European Starling, a
  medium-sized songbird w/ the dark silky plumage
  short triangular wings typical of members of this
  family

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EmbirizidaeSparrows and allies

• small to medium-sized birds
• often brown and streaked
• short, pointed, conical bills
• forage mostly on the ground
• often seen in shrubs

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EmbirizidaeSparrows allies

• large group of mostly small (some medium-sized),
  streaked brownish birds of grassy brushy areas
• often seen in shrubs
• short, conical, pointed bills
• most switch their diet seasonally, from mostly
  insects larvae in summer to mostly seeds in
  winter
• many forage on the ground using a
  double-scratch method of kicking both feet back
  simultaneously to expose food
• some species form large, pure or mixed flocks in
  winter, while others have very specific habitat
  requirements do not flock

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FringillidaeFinches and allies

• small to medium-sized birds
• sexually dimorphic
• stout, conical bill (crossed in 2 species)
• emarginate tail
• undulating, fast flight
• long, complex songs
• often forest birds

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FringillidaeSiskins, Crossbills, allies

• small to medium-sized birds
• often forest birds
• stout, conical (sparrow-like) bill (crossed in 2
  sp.)
• usually short emarginated (notched) tail
• sexually dimorphic males often brightly colored
  w/ patches of red or yellow females drabber
• constantly give distinctive calls in high,
  strong, fast undulating flight often perch in
  treetops
• long, complex songs

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PasseridaeOld World Sparrows

• introduced from Europe
• similar to emberizine sparrows
• small birds
• stout, conical bill
• no well-developed song often repeat
  single elements