- Cabanis's Bunting
- Cabanis's Greenbul
- Cabanis's Ground Sparrow
- Cabanis's Wren
- Calandra Lark
- California Quail
- Canada Goose
- Canary Islands Stonechat
- Cape Batis
- Cape Canary
- Cape Crow
- Cape Eagle-Owl
- Cape Grassbird
- Cape May Warbler
- Cape Robin-Chat
- Cape Rock Thrush
- Cape Teal
- Cape Wagtail
- Cape White-eye
- Capped Wheatear
- Cardinal Quelea
- Cardinal Woodpecker
- Carrion Crow
- Caspian Gull
- Caspian Plover
- Caspian Tern
- Cassin's Flycatcher
- Cassin's Honeybird
- Cave Swallow
- Cetti's Warbler
- Changeable Hawk-Eagle
- Charming Hummingbird
- Chestnut-backed Antbird
- Chestnut-backed Owlet
- Chestnut-backed Sparrow-Lark
- Chestnut-banded Plover
- Chestnut-bellied Sandgrouse
- Chestnut-bellied Starling
- Chestnut-capped Warbler
- Chestnut-crowned Sparrow-Weaver
- Chestnut-fronted Helmetshrike
- Chestnut-headed Bee-eater
- Chestnut-headed Sparrow-Lark
- Chestnut-sided Warbler
- Chestnut-throated Apalis
- Chestnut Sparrow
- Chestnut Wattle-eye
- Chestnut Weaver
- Chilean Mockingbird
- Chilean Pigeon
- Chilean Seaside Cinclodes
- Chilean Swallow
- Chiloe Wigeon
- Chimango Caracara
- Chinspot Batis
- Chubb's Cisticola
- Cinereous Tit
- Cinereous Vulture
- Cinnamon-breasted Bunting
- Cinnamon-chested Bee-eater
- Cinnamon Becard
- Cinnamon Bracken Warbler
- Cinnamon Teal
- Cinnamon Woodpecker
- Cirl Bunting
- Clamorous Reed Warbler
- Clarke's Weaver
- Clay-colored Thrush
- Coal Tit
- Cockatiel
- Cocoa Woodcreeper
- Collared Aracari
- Collared Flycatcher
- Collared Pratincole
- Collared Sunbird
- Collared Trogon
- Collared Whitestart
- Common Black Hawk
- Common Blackbird
- Common Bulbul
- Common Buzzard
- Common Buzzard (vulpinus)
- Common Chiffchaff
- Common Chlorospingus
- Common Crane
- Common Cuckoo
- Common Eider
- Common Emerald Dove
- Common Firecrest
- Common Gallinule
- Common Goldeneye
- Common Grasshopper Warbler
- Common Greenshank
- Common Ground Dove
- Common Gull
- Common Iora
- Common Kestrel
- Common Kingfisher
- Common Linnet
- Common Loon
- Common Merganser
- Common Moorhen
- Common Myna
- Common Nightingale
- Common Ostrich
- Common Pheasant
- Common Pochard
- Common Redpoll
- Common Redshank
- Common Redstart
- Common Reed Bunting
- Common Reed Warbler
- Common Reed Warbler (baeticatus)
- Common Ringed Plover
- Common Rock Thrush
- Common Sandpiper
- Common Scimitarbill
- Common Scoter
- Common Shelduck
- Common Snipe
- Common Starling
- Common Swift
- Common Tailorbird
- Common Tern
- Common Tody-Flycatcher
- Common Waxbill
- Common Whitethroat
- Common Wood Pigeon
- Common Yellowthroat
- Compact Weaver
- Copper Sunbird
- Coppersmith Barbet
- Coppery-headed Emerald
- Coqui Francolin
- Corn Bunting
- Corsican Finch
- Costa Rican Swift
- Crab-plover
- Crested Barbet
- Crested Caracara (cheriway)
- Crested Francolin
- Crested Guan
- Crested Honey Buzzard
- Crested Lark
- Crested Serpent Eagle
- Crested Tit
- Crested Treeswift
- Crimson-collared Tanager
- Crimson-fronted Barbet
- Crimson-rumped Waxbill
- Croaking Cisticola
- Crowned Eagle
- Crowned Hornbill
- Crowned Lapwing
- Crowned Sandgrouse
- Crowned Woodnymph
- Cuban Amazon
- Cuban Blackbird
- Cuban Bullfinch
- Cuban Emerald
- Cuban Green Woodpecker
- Cuban Martin
- Cuban Pewee
- Cuban Pygmy Owl
- Cuban Tody
- Cuban Vireo
- Cuckoo-finch
- Curlew Sandpiper
- Cut-throat Finch