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Regional Birds
This guide to birds of Boulder County, Colorado features beautiful photos of every bird species likely to be seen in Boulder County.
If you’d also like a printable checklist, download the Boulder County Checklist from the Colorado Field Ornithologists (2013 version; PDF).
Quick Links to Groups
Gerhard Assenmacher, Stephen Jones, and Amy Schlotthauer worked together to make this online field guide possible. Stephen Jones collated all the status, population, and conservation information for each bird. A list of all the photographic contributors is at the end of this page.
The distribution and status of birds in Boulder County is ever-changing. If you find incorrect information or would like to contribute additional information or images to this guide, please contact us.
The expanded version of each image bears a copyright notice, photographer’s name, and information about each species. Please respect these specific copyrights if you choose to use them elsewhere.
Swans, Geese and Ducks
American Wigeon (m)
American Wigeon (f)
Blue-winged Teal pair
Canada Goose
Gadwall
Greater White-fronted Goose
Mallard (m)
Mallard (f)
Northern Shoveler
Snow Goose
Trumpeter Swan
Tundra Swan
Northern Pintail (m)
Northern Pintail (f)
Green-winged Teal
Canvasback (m)
Canvasback (f)
Ring-necked Duck (m)
Ring-necked Duck (f)
Greater Scaup (m)
Greater Scaup (f)
Lesser Scaup (m)
Lesser Scaup (f)
Long-tailed Duck
Surf Scoter
Bufflehead (m)
Bufflehead (f)
Common Goldeneye (male)
Common Goldeneye (female)
Hooded Merganser
Barrow's Goldeneye (m)
Barrow's Goldeneye (f)
Common Merganser (m)
Common Merganser (f)
Ruddy Duck
Wood Duck pair
Cinnamon Teal pair
Red-breasted Merganser pair
Pheasants and Grouse
Ring-necked Pheasant
White-tailed Ptarmigan (winter plumage)
Dusky Grouse
Dusky Grouse
Wild Turkey
Loons and Grebes
Common Loon
Pied-billed Grebe
Horned Grebe
Horned Grebe (breeding)
Eared Grebe (breeding)
Eared Grebe
Clark's Grebe
Western Grebe
Double-crested Cormorant
Bittern, Herons, Ibis
American Bittern
Great Blue Heron
Black-crowned Night Heron
Green Heron
Snowy Egret
Great Egret
White-faced Ibis (breeding plumage)
White-faced Ibis (non-breeding)
Vultures, Hawks, Eagles and Falcons
Turkey Vulture
Osprey
Bald Eagle
Golden Eagle
American Goshawk
Sharp-shinned Hawk (juvenile)
Cooper's Hawk
Cooper's Hawk (juvenile)
Swainson's Hawk
Swainson's Hawk (juvenile)
Red-tailed Hawk with young
Rough-legged Hawk
Northern Harrier
American Kestrel (m)
American Kestrel (f)
Peregrine Falcon
Prairie Falcon
Ferruginous Hawk
Rails, Coot and Crane
Virginia Rail
American Coot
Sora
Sora (juvenile)
Sandhill Crane
Sandhill Crane
Shorebirds
Killdeer
Red-necked Phalarope
Wilson's Phalarope
American Avocet (male and female)
American Avocet (non-breeding)
Western Sandpiper
Wilson's Snipe
Baird's Sandpiper
Marbled Godwitt
Lesser Yellowlegs
Greater Yellowlegs
Solitary Sandpiper
Spotted Sandpiper
Semipalmated Plover
Semipalmated Sandpiper
Black-necked Stilt
Gulls and Terns
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Ring-billed Gull
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Lesser Black-backed Gull
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Bonaparte's Gull
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Iceland Gull (Thayer's Gull Subspecies)
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Short-billed Gull
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Herring Gull
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California Gull
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Franklin's Gull
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Black Tern
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Forster's Tern
Pigeons and Doves
Owls
Barn Owl
Boreal Owl
Northern Saw-whet Owl
Short-eared Owl
Long-eared Owl
Burrowing Owl
Northern Pygmy-Owl
Great Horned Owl
Eastern Screech-Owl
Flammulated Owl
Nighthawks, Swifts, Hummingbirds and Kingfisher
Common Nighthawk
Common Nighthawk
Common Poorwill
White-throated Swift
Chimney Swift
Broad-tailed Hummingbird
Rufous Hummingbird
Belted Kingfisher
Woodpeckers
Shrikes, Flycatchers and Vireos
Corvids
Larks and Swallows
Chickadees, Nuthatches and Creeper
Wrens, Gnatcatcher, Kinglets and Dipper
Thrushes
Starling, Pipit, Waxwings
Warblers
Towhees and Sparrows
Tanager, Grosbeaks, Bunting, Blackbirds
Finches and Weaver Finch
The Boulder County Audubon Society greatly appreciates the images donated below. This page extensively features the photographs of Gerhard Assenmacher. Most are Gerhard’s photos, but he wants to acknowledge the following photographers who also contributed to this project:
Kevin Smith
Matthew Studebaker
Tom Wiberding
Don Whittaker