Orders & Selected Families of Birds

This (or any) taxonomy of birds is always in flux because new evidence may lead to a re-examination of relationships.  In addition, the interpretation of the existing data is not always agreed upon. Keep in mind that texts/authorities differ on the specifics of some of the orders, genera, and families.  The taxonomy presented here is based on the International Ornithology Counsel’s (IOC) World Bird List (Version 2.1).  For more information see: Worldbirdnames.org.  

Subclass Palaeognathae: mostly flightless, cursorial birds

1. Tinamiformes (Tinamous) - Great Tinamou

• reduced keel, but only order in Palaeognathae that can fly
• 4 toes (no reduction, unlike other specialized cursorial birds)
• chicken-like bills
• restricted to C. & S. America

Ratites – following 4 orders

• ratite is latin for raft --refers to their flat breastbone, lacking a keel
• flightless, cursorial birds
• male has intromittent organ (penis)
• feathers loose due to lack of hooks on barbules of feathers

2. Struthioniformes (Ostrich)

• largest bird in weight/height (up to 130 kg, 2.75 m)
• fastest runner (up to 50 km/hr, 70 km/hr in straight sprint)
• strong muscular legs; reduced # of toes (2)
• feathers cover whole body, not in tracts; neck and head not feathered
• found only in Africa (except for introduced birds elsewhere)

3. Rheiformes (Rheas) - Greater Rhea

• similar to Ostrich but found in So. America and much smaller (weighs less than half as much)
• feathered neck and head
• longer wings than other ratites (strong claw on each wing)
• no rectrices; 3 toes only; good eyesight & hearing

4. Casuariiformes (Cassowaries & Emus) 

Dromaiidae (Emus)  - Emu

• 3 toes only
• aftershaft present, almost as long as main feather
• flat bill
• 2nd to Ostrich in size (length); found in Australia

Casuariidae (Cassowaries) - Southern Cassowary

• 3 toes only; aftershafts present, almost as long as main feather; flat bill.
• 2nd to Ostrich in weight
• have casque or helmet -- protuberance at top of head; lack rectrices
• found in Australia and New Guinea

5. Apterygiformes (Kiwis) - Brown Kiwi

• no rectrices; no aftershafts present; hair-like feathers; HUGE eggs:  25% body weight
• basically nocturnal; poor eyesight, good sense of hearing & smell
• 4 toes; long, down-curved, flexible bill; nostrils at tip, valves at base
• found in New Zealand

Subclass Neognathae: everything else

6. Galliformes (Grouse, Turkey, Quail, Ptarmigan, Pheasant, and other chicken-like birds) - Gambel's Quail ; Willow Ptarmigan

• medium to large terrestrial species; strong legs, heavy feet
• hind toe always present, often raised above ground
• bill short, conical w/ curved culmen
• large clutches, precocial young; often cryptically colored; large muscular gizzard
• Worldwide distribution

7. Anseriformes (Swans, Geese, Ducks, Screamers)

• aquatic / semi-aquatic birds that swim and fly well
• short-legged, long-necked; feathered oil-gland; precocial young
• Worldwide 
• webbed feet (partially webbed in screamers)

Anatidae (Swans, Geese and Ducks) - Barnacle & Canada Geese, Common Goldeneye 

• bill flat, wide, rounded at end w/ combed serrations at edges
• legs short w/ 3 toes webbed

Anhimidae: (Screamers) - Southern Screamer

• head crested, hooked, chicken-like bill; heavy legs; partial webbing
• 2 spurs at bends in wing

8. Sphenisciformes (Penguins) - King Penguin; Fiordland-crested Penguin

• flightless, but well-developed keel – marine diving birds; chunky
• flattened wings w/ fused bones -can't be folded in normal manner (flippers)
• plumage dense & waterproof – feathers not in tracts; heavy layer of fat
• webbed feet – far back on body, enables upright posture
• Southern Hemisphere

9. Gaviiformes (Loons) - Common Loon

• duck-like aquatic birds -- eat mostly fish, breed in fresh water, spend winter on ocean
• legs far back on body – foot-propelled diving birds (like Podicipediformes)
• 3 front toes fully webbed; spear-shaped bills
• plumage heavy & waterproof; long-lived, monogamous
• males and females monomorphic; both with alternate and basic plumage
• Holarctic

10. Procellariiformes (Petrels, Shearwaters, Storm-Petrels & Albatrosses); Wilson's Storm-Petrel, Black-vented Shearwater

• tube-nosed (tubular nostrils) seabirds (many w/ long thin wings, held stiffly for soaring)
• hooked bill
• well-developed sense of smell; plumage dense, waterproof
• gland for concentrating & excreting salt – in orbit
• 3 front toes webbed
• single egg w/ long incubation period – long-lived
• all oceans – more common in southern hemisphere

11. Podicipediformes (Grebes) - Red-necked Grebe

• aquatic, diving fish-eaters; foot-propelled diving birds
• legs far back on body – facilitates swimming, makes walking on land difficult
• tail reduced; dense, satiny plumage; feathers waterproof due to oily secretions
• eat own feathers! the feathers trap fish bones which are digested or regurgitated
• floating nests; carry young on backs
• Worldwide

12. Phoenicopteriformes (Flamingos) - Greater Flamingo

• wading birds w/ very long legs and neck
• bill unique – bent abruptly downward in middle; serrated edge; thick fleshy tongue
• maxilla, or upper bill segment, moves; mandible (lower bill segments) is almost rigid
• front toes webbed; produce "milk" like pigeon milk; more or less pink; clutch size =1
• Tropics, expect Australia

13. Phaethontiformes (Tropicbirds) Red-billed Tropicbird

• tropical, pelagic (open ocean) species
• largely white; very long tails
• plunge-diving fish-eaters; strong, stout bills

14. Ciconiiformes (Storks)

Ciconiidae (Storks) - Marabou Stork

• large, long-legged, long-necked; long, stout bills
• serially monogamous
• lack syrinx – mute; engage in bill clattering
• employ thermal soaring, gliding flight
• large, stick nests

15. Pelecaniformes (Pelicans, Cormorants, Boobies, Herons, Egrets, Ibises,) - Red-footed Booby; Anhinga

• diverse; medium to large aquatic birds; mostly fish-eaters
• webbed feet - totipalmate
• most are colonial nesters
• Worldwide, more common in tropics

Pelecanidae (pelicans) -Brown Pelican

• dive & scoop to get prey
• very large gular pouch (some species cooperate - herd fish)
• expandable pouch

Phalacrocoracidae (Cormorants) - Pelagic Cormorant

• pursue prey underwater; elongate body, neck, tail
• long, thin, tubular bill, strongly hooked

Ardeidae (Herons, Bitterns and Egrets) -Little Blue Heron

• largest family
• specialized vertebrae: allow spearing, folding neck into "S"
• long, spear-shaped bills (eat fish, frogs)
• have powder down which aid in feather care

Threskiornithidae (Ibises & Spoonbills) -White Ibis

• grooved bills (Ibises – long, curved bills; Spoonbills – flat, spatulate bills)

16. Accipitriformes (Eagles, Hawks, New World Vultures)

• sharp, pointed, heavily curved culmens
• cosmopolitan distribution
• carnivorous

Accipitridae: (Hawks & Eagles) - Bald Eagle

• wings broad & rounded; short necks
• cere & eye-ring bare – often brightly colored
• sharp, powerful talons
• reversed sexual size dimorphism
• excellent vision

Cathartidae: (New World Vultures) – might not belong within this order - Black Vulture

• large with long, broad wings // employ thermal soaring, gliding flight
• carrion feeders
• head & neck bare; lack syrinx
• perforated nostrils
• good sense of smell

17. Falconiformes (Falcons)

Falconidae: (Falcons) - Merlin

• wings long & pointed; bill short, hooked; cere & eye-ring bare
• diurnal birds of prey – excellent fliers, capable of fast flight
• short, strongly hooked bills; sharp, curved talons (claws)
• semiprecocial young (downy, eyes open, but dependent for long time)

*18.  Otidiformes: (Bustards)

• large, terrestrial species; omnivorous
• inhabit dry, open areas; nest on ground; wary
• many endangered due to habitat loss
• Old World only
• strong legs with big toes; long, broad, “fingered” wings

*19. Mesitornithiformes: (Mesites)

• endemic to Madagascar; all 3 species are designated “vulnerable”
• nearly flightless; ground feeders
• pheasant-like in appearance though brownish with paler undersides
• possess powder down

*20. Cariamiformes: (Seriemas)

• So. America – only 2 species
• long legs, necks, and tails, but short wings; somewhat like a small crane (~2.5 ft. in length)
• ground foragers; run (rather than fly) from danger; inhabit open areas
• brownish with short bills and erectile crests
• have an extensible second claw that can be used to tear apart prey

*21. Eurypygiformes: (Kagu, Sunbittern)

• long legs and relatively long, pointed bills; medium-sized
• possess powder down
• elaborate wing displays
• carnivorous

Eurypygidae (Sunbittern)

• Cent. – So. America
• heron-like with relatively long legs and neck; hunts vertebrates along edges of streams
• semi-precocial young
• subdued, camouflaged plumage; concealed, flashy coloration on spread wings used for startle, threat, or courtship displays

Rhinochetidae (Kagu)

• endemic to New Caledonia; rare & endangered
• terrestrial, nearly flightless
• ash-gray and white with bright pink legs and bill; long crest used in displays
• only bird species that possesses nasal corns (cover the nostrils)
• only 1/3 number of red blood cells but 3X the amount of hemoglobin / rbc as other birds

22. Gruiformes (Cranes, Rails, Coots and allies) -Virgina Rail; Sandhill Crane; American Coot

• no crop; most with oil gland; primarily precocial young
• very diverse – shared features of palate and skeleton
• many aquatic; many shy, hard-to-see species
• Worldwide

23. Charadriiformes (Plovers, Sandpipers, Gulls, Terns, Alcids, and allies)

• waders, swimmers, divers (all water birds or derived from water birds)
• all have distinct palate, syringeal muscles, and vertebral column
• Worldwide
• very diverse; many bear no outward resemblence to each other

Scolopacidae (Sandpipers) - Sanderling

• wading birds with long slender bills

Charadriidae (Plovers) - Semipalmated Plover

• waders but with stubby bills, often swollen at tip
• short thick necks

Laridae (Gulls & Terns) --Herring Gull

• water birds with long, pointed wings; webbed feet
• many well-adapted to humans and their constructs (dumps)

Alcidae (Puffins, Auks, Murres and Guillemots) - Parakeet & Least Auklets

• small medium-sized seabirds with chunky bodies, short necks; pointed wings
• short legs set far back on body; 3 front toes webbed; often black & white
• Northern oceans

*24. Pteroclidiformes: (Sandgrouse)

• strictly Old World; total of 16 species
• inhabit open, treeless habitats (plains and semi-deserts)
• gregarious; ground-feeding seed-eaters
• belly feathers adapted for absorbing and retaining water
• small pigeon-like heads and necks with sturdy, compact bodies
• long, pointed wings with short, feathered legs
• cryptic plumage
• monogamous; precocial young

25. Columbiformes (Doves & Pigeons) -Mourning Dove

• plump-bodies with small heads, short bills, short legs
• large crop -- produces crop milk (for offspring)
• clutch size = 2; biparental care
• Worldwide

26. Psittaciformes (Parakeets, Macaws, Parrots, Lories) -Monk Parakeet

• large-headed, short-necked; social and vocal
• heavy, hooked bills -- upper mandible (maxilla) quite mobile, hinged to skull
• legs short, feet strong
• zygodactyl feet (2 toes up and 2 back) for perching and climbing
• Primarily Pantropical (few temperate)

27. Opisthocomiformes (Hoatzin)

• vegetarian specialist, large crop for fermentation of leaves
• weak flier; wing claws in young
• So. America

*28. Musophagiformes (Turacos & Plantain-eaters) - White-crested Turacos

• medium size
• long tails, arboreal
• outer toe reversible - not truly zygodactyl
• unique color pigments - turacoverdin & turacin
• well-developed wing claws in young
• forest & woodlands of Africa

29. Cuculiformes (Cuckoos, Anis, Roadrunners)

Cuculidae (Cuckoos & roadrunners) - Yellow-billed Cuckoo

• slender, long-tailed (usually); bill usually thin and down-curved
• zygodactyl feet; 8-10 (instead of 10-14) rectrices
• Worldwide; Old World species are parasitic

30. Strigiformes (Owls)

• mostly nocturnal birds of prey; small, heavily decurved bills
• strong feet with long sharp claws; zygodactyl toes
• large heads & eyes with facial disks that concentrate sound & increase hearing sensitivity
• asymmetrical ear openings in some – improves localization ability
• specialized telescopic vision
• often feathered legs and toes; outer toe can be reversed
• soft specialized plumage -- muffles sound; cryptically colored
• eyes fixed – turn head from side to side (up to 270 degrees)
• Worldwide

Strigidae (typical owls) - Boreal Owl

Tytonidae (Barn-Owls)

• heart-shaped face
• lighter plumage, on average (sometimes nearly white)

31. Caprimulgiformes (Nightjars & Nighthawks and allies) - Chuck Will's Widow

• nocturnal or crepuscular
• soft plumage, usually cryptic; often long bristles surrounding bill
• short weak legs and feet; long pointed wings; flight strong but erratic
• small bill with wide gape; clutch size 1 or 2
• Worldwide

32. Apodiformes (Swifts & Hummingbirds)

• small or very small birds with tiny feet; very accomplished fliers
• very small humerus; 10 long primaries, short secondaries
• clutch size 1 or 2

Apodidae: (Swifts) - Chimney Swift

• tiny bill; gregarious; insect-feeder; sexually monomorphic
• nest on sides of cliffs, caves, hollow trees, chimneys
• Worldwide

Trochilidae: (Hummingbirds) - Ruby-throated Hummingbird

• long slender bill; nectar-feeders; solitary
• very agile fliers; sexually dimorphic
• New World

33. Coliiformes (Mousebirds) - Speckled Mousebird

• small, crested birds with very long tails -- brown, gray
• pamprodactyl feet (toes 1 & 4 reversible)
• lack apteria (featherless regions)
• restricted to Africa

34. Trogoniformes (Trogons & Quetzals) - Elegant Trogon

• short, wide bills, fruit-eating; very colorful, often iridescent
• short wings, long tails, cavity nesters
• small, weak feet; heterodactyl feet (toes 1 & 2 back, 3 & 4 up)
• Pantropical, excluding Australasia

*35. Leptosomatiformes (Cuckoo Roller)

• limited to a single species (though sometimes one of the subspecies is considered a separate species)
• arboreal species found only on Madagascar and the Comoro Islands
• approximately 1.5 ft. in length; sexually dichromatic (males – grayish, females – brownish)
• small legs & feet with zygodactylous toe arrangement (with 4^th toe reversible, similar to Musophagiformes)
• large head; stout bill; carnivorous
• small eyes set far back on face
• cavity nesters

36. Coraciiformes (Kingfishers, Rollers, Hornbills, Bee-eaters, & allies) -Green Kingfisher

• mostly stocky birds with large heads, small feet
• conspicuous; brightly colored; many gregarious and noisy
• syndactyl feet (two toes 2 & 3 partially fused); mostly long prominent bill; carnivorous
• hole-nesters; altricial young; often cooperative breeders
• Worldwide

*37. Bucerotiformes (Hornbills, Hoopoe, Woodhoopoes)

• medium to large birds with relatively large heads
• Old World
• monogamous
• omnivorous; long, down-curved bills, though some very broad and others thin
• cavity nesters

Bucerotidae (Hornbills)

• huge, thick bills, often with a casque on the upper mandible
• 2-lobed kidney
• 1^st two vertebrae fused
• sexually dimorphic

Upupidae (Hoopoe)

• uniquely shaped stapes (shared with Phoeniculidae)
• single species (sometimes divided into 2 or 3 species)
• long, thin bill with well developed head musculature
• long crest; buffy orange plumage with black and white striped remiges
• forages on the ground

Phoeniculidae (Woodhoopoes & Scimitar-bills)

• uniquely shaped stapes (shared with Upupidae)
• long tails
• metallic (blue, green, or purple) plumage
• move up tree trunks like woodpeckers; hop when foraging on ground

38. Piciformes (Woodpeckers, Toucans, Puffbirds, and allies)-Hairy Woodpecker

• zygodactyl feet; long, barb-tipped tongues; pointed, stiff rectrices
• unique arrangement of tendons in toes
• very diverse bill shapes
• cavity nesters; altricial young
• Worldwide, excluding Australasia

39. Passeriformes (Perching Birds)

• by far the largest order – contains more than ½ of the world’s birds
• mostly small landbirds with 4 unwebbed toes -3 up, 1 back (anisodactyl)
• enlarged and flexible hallus
• distinctive, spiral-shaped sperm;
• higher metabolism; reduced number of neck vertebrae; distinctive bony palate
• relatively large brains; superior learning (especially vocal) abilities
• Worldwide

Suborder: Tyranni (Suboscines)

• simpler arrangement of syringeal muscles than Oscines

Tyrannidae: Tyrant flycatchers (including phoebes, pewees, and kingbirds) - - Eastern Wood-Pewee

Suborder: Passeres (Oscines) - songbirds

• complex vocal musculature; learn song

Vireonidae:  Vireos (Yellow-throated Vireo)

Corvidae:  Crows, Jays (Blue Jay), Magpies

Bombycillidae:  Waxwings (Cedar Waxwing)

Paridae: Titmice (Tufted Titmouse), Chickadees (Carolina Chickadee)

Alaudidae:  Larks (Horned Lark)

Hirundinidae:  Swallows, Martins (Tree Swallow, Purple Martin)

Regulidae:  Kinglets (Ruby-crowned Kinglet)

Troglodytidae:  Wrens (Sedge Wren)

Polioptilidae:  Gnatcatchers (Blue-gray Gnatcatcher)

Sittidae:  Nuthatches (Red-breasted Nuthatch & White-breasted Nuthatch)

Certhiidae:  Creepers (Brown Creeper)

Mimidae:  Mimics--Catbirds, Thrashers, Mockingbirds  (Northern Mockingbird)

Sturnidae:  Starlings (European Starling)

Turdidae:  Thrushes (Eastern Bluebird)

Passeridae:  Old World Sparrows (House Sparrow)

Motacillidae:  Pipits (American Pipit)

Fringillidae:  Finches (Purple Finch)

Parulidae:  New World Warblers (Common Yellowthroat)

Icteridae:  New World Orioles, Blackbirds and allies (Red-winged Blackbird)

Emberizidae:  Sparrows, Juncos, Towhees (Song Sparrow)

Thraupidae: Tanagers (Scarlet Tanager)

Calcariidae: Longspurs and Snow Buntings

Cardinalidae:  Cardinals, Buntings, and Grosbeaks (Northern Cardinal)