Colorado - 493 species
WHISTLING-DUCKS
Black-bellied Whistling-Duck
Fulvous Whistling-Duck
GEESE
Greater White-fronted Goose
Snow Goose
Ross's Goose
Brant
Cackling Goose
Canada Goose
SWANS
Trumpeter Swan
Tundra Swan
DUCKS
Wood Duck
Gadwall
Eurasian Wigeon
American Wigeon
American Black Duck
Mallard
Blue-winged Teal
Cinnamon Teal
Northern Shoveler
Northern Pintail
Garganey
Green-winged Teal
Canvasback
Redhead
Ring-necked Duck
Tufted Duck
Greater Scaup
Lesser Scaup
Harlequin Duck
Surf Scoter
White-winged Scoter
Black Scoter
Long-tailed Duck
Bufflehead
Common Goldeneye
Barrow's Goldeneye
Hooded Merganser
Common Merganser
Red-breasted Merganser
Ruddy Duck
QUAIL
Scaled Quail
Gambel's Quail
Northern Bobwhite
PARTRIDGES
Chukar
PHEASANTS
Ring-necked Pheasant
GROUSE
Ruffed Grouse
Greater Sage-Grouse
Gunnison Sage-Grouse
White-tailed Ptarmigan
Dusky Grouse
Sharp-tailed Grouse
Greater Prairie-Chicken
Lesser Prairie-Chicken
TURKEYS
Wild Turkey
LOONS
Red-throated Loon
Arctic Loon
Pacific Loon
Common Loon
Yellow-billed Loon
GREBES
Pied-billed Grebe
Horned Grebe
Red-necked Grebe
Eared Grebe
Western Grebe
Clark's Grebe
STORKS
Wood Stork
FRIGATEBIRDS
Magnificent Frigatebird
CORMORANTS
Neotropic Cormorant
Double-crested Cormorant
DARTERS
Anhinga
PELICANS
American White Pelican
Brown Pelican
HERONS
American Bittern
Least Bittern
Great Blue Heron
Great Egret
Snowy Egret
Little Blue Heron
Tricolored Heron
Reddish Egret
Cattle Egret
Green Heron
Black-crowned Night-Heron
Yellow-crowned Night-Heron
IBISES
White Ibis
Glossy Ibis
White-faced Ibis
Roseate Spoonbill
VULTURES
Black Vulture
Turkey Vulture
HAWKS
Osprey
Swallow-tailed Kite
Mississippi Kite
Bald Eagle
Northern Harrier
Sharp-shinned Hawk
Cooper's Hawk
Northern Goshawk
Common Black-Hawk
Harris's Hawk
Red-shouldered Hawk
Broad-winged Hawk
Swainson's Hawk
Zone-tailed Hawk
Red-tailed Hawk
Ferruginous Hawk
Rough-legged Hawk
Golden Eagle
RAILS
Yellow Rail
Black Rail
King Rail
Virginia Rail
Sora
Purple Gallinule
Common Gallinule
American Coot
CRANES
Sandhill Crane
Whooping Crane
PLOVERS
Black-bellied Plover
American Golden-Plover
Snowy Plover
Semipalmated Plover
Piping Plover
Killdeer
Mountain Plover
AVOCETS & STILTS
Black-necked Stilt
American Avocet
SANDPIPERS
Spotted Sandpiper
Solitary Sandpiper
Greater Yellowlegs
Willet
Lesser Yellowlegs
Upland Sandpiper
Eskimo Curlew
Whimbrel
Long-billed Curlew
Hudsonian Godwit
Marbled Godwit
Ruddy Turnstone
Red Knot
Sanderling
Semipalmated Sandpiper
Western Sandpiper
Least Sandpiper
White-rumped Sandpiper
Baird's Sandpiper
Pectoral Sandpiper
Sharp-tailed Sandpiper
Dunlin
Curlew Sandpiper
Stilt Sandpiper
Buff-breasted Sandpiper
Ruff
Short-billed Dowitcher
Long-billed Dowitcher
Wilson's Snipe
American Woodcock
Wilson's Phalarope
Red-necked Phalarope
Red Phalarope
GULLS
Black-legged Kittiwake
Ivory Gull
Sabine's Gull
Bonaparte's Gull
Black-headed Gull
Little Gull
Ross's Gull
Laughing Gull
Franklin's Gull
Mew Gull
Ring-billed Gull
Western Gull
California Gull
Herring Gull
Thayer's Gull
Iceland Gull
Lesser Black-backed Gull
Slaty-backed Gull
Glaucous-winged Gull
Glaucous Gull
Great Black-backed Gull
Kelp Gull
TERNS
Sooty Tern
Least Tern
Caspian Tern
Black Tern
Common Tern
Arctic Tern
Forster's Tern
Royal Tern
SKIMMERS
Black Skimmer
JAEGERS
Pomarine Jaeger
Parasitic Jaeger
Long-tailed Jaeger
MURRELETS
Long-billed Murrelet
Ancient Murrelet
PIGEONS & DOVES
Rock Pigeon
Band-tailed Pigeon
Eurasian Collared-Dove
White-winged Dove
Mourning Dove
Inca Dove
Common Ground-Dove
CUCKOOS
Yellow-billed Cuckoo
Black-billed Cuckoo
Greater Roadrunner
Groove-billed Ani
BARN OWLS
Barn Owl
OWLS
Flammulated Owl
Western Screech-Owl
Eastern Screech-Owl
Great Horned Owl
Snowy Owl
Northern Pygmy-Owl
Burrowing Owl
Spotted Owl
Barred Owl
Long-eared Owl
Short-eared Owl
Boreal Owl
Northern Saw-whet Owl
NIGHTJARS
Lesser Nighthawk
Common Nighthawk
Common Poorwill
Eastern Whip-poor-will
Mexican Whip-poor-will
SWIFTS
Black Swift
Chimney Swift
White-throated Swift
HUMMINGBIRDS
Green Violetear
Magnificent Hummingbird
Blue-throated Hummingbird
Ruby-throated Hummingbird
Black-chinned Hummingbird
Anna's Hummingbird
Costa's Hummingbird
Broad-tailed Hummingbird
Rufous Hummingbird
Calliope Hummingbird
Broad-billed Hummingbird
White-eared Hummingbird
KINGFISHERS
Belted Kingfisher
WOODPECKERS
Lewis's Woodpecker
Red-headed Woodpecker
Acorn Woodpecker
Red-bellied Woodpecker
Williamson's Sapsucker
Yellow-bellied Sapsucker
Red-naped Sapsucker
Ladder-backed Woodpecker
Downy Woodpecker
Hairy Woodpecker
American Three-toed Woodpecker
Northern Flicker
FALCONS
Crested Caracara
American Kestrel
Merlin
Gyrfalcon
Peregrine Falcon
Prairie Falcon
FLYCATCHERS
Olive-sided Flycatcher
Western Wood-Pewee
Eastern Wood-Pewee
Yellow-bellied Flycatcher
Acadian Flycatcher
Alder Flycatcher
Willow Flycatcher
Least Flycatcher
Hammond's Flycatcher
Gray Flycatcher
Dusky Flycatcher
Cordilleran Flycatcher
Buff-breasted Flycatcher
Black Phoebe
Eastern Phoebe
Say's Phoebe
Vermilion Flycatcher
Dusky-capped Flycatcher
Ash-throated Flycatcher
Great Crested Flycatcher
Brown-crested Flycatcher
Sulphur-bellied Flycatcher
Cassin's Kingbird
Thick-billed Kingbird
Western Kingbird
Eastern Kingbird
Scissor-tailed Flycatcher
SHRIKES
Loggerhead Shrike
Northern Shrike
VIREOS
White-eyed Vireo
Bell's Vireo
Gray Vireo
Yellow-throated Vireo
Plumbeous Vireo
Cassin's Vireo
Blue-headed Vireo
Warbling Vireo
Philadelphia Vireo
Red-eyed Vireo
JAYS & CROWS
Gray Jay
Pinyon Jay
Steller's Jay
Blue Jay
Western Scrub-Jay
Clark's Nutcracker
Black-billed Magpie
American Crow
Chihuahuan Raven
Common Raven
LARKS
Horned Lark
SWALLOWS
Purple Martin
Tree Swallow
Violet-green Swallow
Northern Rough-winged Swallow
Bank Swallow
Cliff Swallow
Barn Swallow
CHICKADEES
Black-capped Chickadee
Mountain Chickadee
Juniper Titmouse
BUSHTITS
Bushtit
NUTHATCHES
Red-breasted Nuthatch
White-breasted Nuthatch
Pygmy Nuthatch
CREEPERS
Brown Creeper
WRENS
Rock Wren
Canyon Wren
House Wren
Pacific Wren
Winter Wren
Sedge Wren
Marsh Wren
Carolina Wren
Bewick's Wren
GNATCATCHERS
Blue-gray Gnatcatcher
DIPPERS
American Dipper
KINGLETS
Golden-crowned Kinglet
Ruby-crowned Kinglet
THRUSHES
Eastern Bluebird
Western Bluebird
Mountain Bluebird
Townsend's Solitaire
Veery
Gray-cheeked Thrush
Swainson's Thrush
Hermit Thrush
Wood Thrush
American Robin
Varied Thrush
THRASHERS
Gray Catbird
Northern Mockingbird
Sage Thrasher
Brown Thrasher
Long-billed Thrasher
Bendire's Thrasher
Curve-billed Thrasher
STARLINGS
European Starling
PIPITS
American Pipit
Sprague's Pipit
WAXWINGS
Bohemian Waxwing
Cedar Waxwing
SILKY-FLYCATCHERS
Phainopepla
LONGSPURS
Lapland Longspur
Chestnut-collared Longspur
Smith's Longspur
McCown's Longspur
Snow Bunting
WARBLERS
Ovenbird
Worm-eating Warbler
Louisiana Waterthrush
Northern Waterthrush
Golden-winged Warbler
Blue-winged Warbler
Black-and-white Warbler
Prothonotary Warbler
Swainson's Warbler
Tennessee Warbler
Orange-crowned Warbler
Lucy's Warbler
Nashville Warbler
Virginia's Warbler
Connecticut Warbler
MacGillivray's Warbler
Mourning Warbler
Kentucky Warbler
Common Yellowthroat
Hooded Warbler
American Redstart
Cape May Warbler
Cerulean Warbler
Northern Parula
Tropical Parula
Magnolia Warbler
Bay-breasted Warbler
Blackburnian Warbler
Yellow Warbler
Chestnut-sided Warbler
Blackpoll Warbler
Black-throated Blue Warbler
Palm Warbler
Pine Warbler
Yellow-rumped Warbler
Yellow-throated Warbler
Prairie Warbler
Grace's Warbler
Black-throated Gray Warbler
Townsend's Warbler
Hermit Warbler
Black-throated Green Warbler
Canada Warbler
Wilson's Warbler
Red-faced Warbler
Painted Redstart
Yellow-breasted Chat
SPARROWS
Green-tailed Towhee
Spotted Towhee
Eastern Towhee
Rufous-crowned Sparrow
Canyon Towhee
Cassin's Sparrow
American Tree Sparrow
Chipping Sparrow
Clay-colored Sparrow
Brewer's Sparrow
Field Sparrow
Black-chinned Sparrow
Vesper Sparrow
Lark Sparrow
Black-throated Sparrow
Sage Sparrow
Lark Bunting
Savannah Sparrow
Grasshopper Sparrow
Baird's Sparrow
Henslow's Sparrow
Le Conte's Sparrow
Nelson's Sparrow
Fox Sparrow
Song Sparrow
Lincoln's Sparrow
Swamp Sparrow
White-throated Sparrow
Harris's Sparrow
White-crowned Sparrow
Golden-crowned Sparrow
Dark-eyed Junco
CARDINALS
Hepatic Tanager
Summer Tanager
Scarlet Tanager
Western Tanager
Northern Cardinal
Pyrrhuloxia
Rose-breasted Grosbeak
Black-headed Grosbeak
Blue Grosbeak
Lazuli Bunting
Indigo Bunting
Painted Bunting
Dickcissel
BLACKBIRDS
Bobolink
Red-winged Blackbird
Eastern Meadowlark
Western Meadowlark
Yellow-headed Blackbird
Rusty Blackbird
Brewer's Blackbird
Common Grackle
Great-tailed Grackle
Bronzed Cowbird
Brown-headed Cowbird
Orchard Oriole
Hooded Oriole
Streak-backed Oriole
Bullock's Oriole
Baltimore Oriole
Scott's Oriole
FINCHES
Brambling
Gray-crowned Rosy-Finch
Black Rosy-Finch
Brown-capped Rosy-Finch
Pine Grosbeak
Purple Finch
Cassin's Finch
House Finch
Red Crossbill
White-winged Crossbill
Common Redpoll
Pine Siskin
Lesser Goldfinch
Lawrence's Goldfinch
American Goldfinch
Evening Grosbeak
OLD WORLD SPARROWS
House Sparrow