- Caatinga Cacholote
- Caatinga Puffbird
- Cabanis's Wren
- Cabot's Tern
- Calandra Lark
- California Condor
- California Quail
- California Scrub Jay
- California Thrasher
- California Towhee
- Campo Flicker
- Canada Goose
- Canary Islands Chiffchaff
- Canary Islands Stonechat
- Canary White-eye
- Cape Barren Goose
- Cape Bunting
- Cape Cormorant
- Cape Crow
- Cape May Warbler
- Cape Robin-Chat
- Cape Sparrow
- Cape Teal
- Cape Verde Shearwater
- Cape Vulture
- Cape Wagtail
- Cape Weaver
- Capped Heron
- Capped Wheatear
- Cardinal Myzomela
- Carib Grackle
- Caribbean Dove
- Caribbean Elaenia
- Carolina Wren
- Carrion Crow
- Caspian Plover
- Cattle Tyrant
- Cave Swallow
- Cave Swiftlet
- Cetti's Warbler
- Chaco Chachalaca
- Chaco Eagle
- Chalk-browed Mockingbird
- Channel-billed Toucan
- Chat Flycatcher
- Chestnut-backed Sparrow-Lark
- Chestnut-bellied Sandgrouse
- Chestnut-bellied Seedeater
- Chestnut-breasted Mannikin
- Chestnut-crowned Antpitta
- Chestnut-eared Aracari
- Chestnut-fronted Helmetshrike
- Chestnut-fronted Macaw
- Chestnut-headed Bee-eater
- Chestnut-sided Warbler
- Chestnut-throated Seedeater
- Chestnut-vented Warbler
- Chestnut-winged Cinclodes
- Chestnut Sparrow
- Chestnut Teal
- Chestnut Weaver
- Chinese Pond Heron
- Chivi Vireo
- Choco Toucan
- Choco Trogon
- Choco Tyrannulet
- Chopi Blackbird
- Chukar Partridge
- Cinereous Conebill
- Cinereous Tit
- Cinereous Vulture
- Cinnamon Becard
- Cinnamon Hummingbird
- Cinnamon Quail-thrush
- Cinnamon Tanager
- Cinnamon Teal
- Cirl Bunting
- Citreoline Trogon
- Clark's Grebe
- Clay-colored Thrush
- Cliff Flycatcher
- Cloven-feathered Dove
- Coal Tit
- Coastal Miner
- Cock-tailed Tyrant
- Cocoi Heron
- Coconut Lorikeet
- Collared Aracari
- Collared Crescentchest
- Collared Inca
- Collared Kingfisher
- Collared Pratincole
- Collared Sunbird
- Collared Warbling Finch
- Comb-crested Jacana
- Comb Duck
- Common Black Hawk
- Common Blackbird
- Common Bronzewing
- Common Bulbul
- Common Buzzard
- Common Cactus Finch
- Common Chiffchaff
- Common Crane
- Common Cuckoo
- Common Eider
- Common Emerald Dove
- Common Firecrest
- Common Gallinule
- Common Goldeneye
- Common Grackle
- Common Grasshopper Warbler
- Common Greenshank
- Common Ground Dove
- Common Gull
- Common Hawk-Cuckoo
- Common Iora
- Common Jery
- Common Kestrel
- Common Linnet
- Common Loon
- Common Merganser
- Common Miner
- Common Moorhen
- Common Murre
- Common Myna
- Common Newtonia
- Common Nightingale
- Common Ostrich
- Common Pheasant
- Common Pochard
- Common Potoo
- Common Quail
- Common Redpoll
- Common Redshank
- Common Redstart
- Common Ringed Plover
- Common Rock Thrush
- Common Sandpiper
- Common Scimitarbill
- Common Shelduck
- Common Snipe
- Common Starling
- Common Swift
- Common Tailorbird
- Common Tern
- Common Tody-Flycatcher
- Common Waxbill
- Common Whitethroat
- Common Wood Pigeon
- Common Woodshrike
- Common Yellowthroat
- Coppersmith Barbet
- Coppery-headed Emerald
- Coppery-tailed Coucal
- Coqui Francolin
- Cordilleran Canastero
- Corn Bunting
- Corsican Finch
- Cory's Shearwater
- Coscoroba Swan
- Cream-colored Courser
- Cream-colored Woodpecker
- Cream-winged Cinclodes
- Crested Barbet
- Crested Bellbird
- Crested Caracara
- Crested Caracara (cheriway)
- Crested Coua
- Crested Drongo
- Crested Duck
- Crested Francolin
- Crested Honey Buzzard
- Crested Lark
- Crested Oropendola
- Crested Owl
- Crested Pigeon
- Crested Serpent Eagle
- Crested Tit
- Crested Treeswift
- Cretzschmar's Bunting
- Crimson-breasted Shrike
- Crimson-crested Woodpecker
- Crimson-rumped Toucanet
- Crimson Finch
- Crimson Rosella
- Croaking Ground Dove
- Crowned Hornbill
- Crowned Lapwing
- Cuban Amazon
- Cuban Blackbird
- Cuban Crow
- Cuban Emerald
- Cuban Pewee
- Cuban Tody
- Cuban Trogon
- Curl-crested Jay
- Curlew Sandpiper