- California Gull
- California Quail
- California Scrub Jay
- Campo Flicker
- Canada Goose
- Cape Barren Goose
- Cape Bunting
- Cape Petrel
- Cape Sparrow
- Cape Starling
- Cape Wagtail
- Cape Weaver
- Cape White-eye
- Capped Heron
- Capped Wheatear
- Cardinal Woodpecker
- Caspian Tern
- Cattle Tyrant
- Chabert Vanga
- Chaco Chachalaca
- Chalk-browed Mockingbird
- Chestnut-backed Sparrow-Lark
- Chestnut-banded Plover
- Chestnut-bellied Guan
- Chestnut-bellied Sandgrouse
- Chestnut-eared Aracari
- Chestnut-naped Francolin
- Chestnut-vented Nuthatch
- Chestnut Teal
- Chilean Skua
- Chimango Caracara
- Chinspot Batis
- Chinstrap Penguin
- Chocolate-backed Kingfisher
- Chopi Blackbird
- Chubb's Cisticola
- Chukar Partridge
- Cinnamon-chested Bee-eater
- Cinnamon Tanager
- Clark's Nutcracker
- Cliff Flycatcher
- Cock-tailed Tyrant
- Cocoi Heron
- Collared Finchbill
- Collared Kingfisher
- Collared Pratincole
- Collared Sunbird
- Comb-crested Jacana
- Common Black Hawk
- Common Blackbird
- Common Bronzewing
- Common Buzzard
- Common Chaffinch
- Common Chiffchaff
- Common Crane
- Common Cuckoo
- Common Eider
- Common Emerald Dove
- Common Gallinule
- Common Goldeneye
- Common Grackle
- Common Greenshank
- Common Kestrel
- Common Kingfisher
- Common Linnet
- Common Loon
- Common Merganser
- Common Moorhen
- Common Murre
- Common Myna
- Common Nightingale
- Common Ostrich
- Common Pheasant
- Common Pochard
- Common Redshank
- Common Reed Bunting
- Common Ringed Plover
- Common Sandpiper
- Common Shelduck
- Common Snipe
- Common Starling
- Common Tern
- Common Wood Pigeon
- Common Yellowthroat
- Copper Sunbird
- Coppersmith Barbet
- Coppery-headed Emerald
- Coppery-tailed Coucal
- Coquerel's Coua
- Coqui Francolin
- Corn Bunting
- Cory's Shearwater
- Crested Barbet
- Crested Black Tyrant
- Crested Coua
- Crested Drongo
- Crested Duck
- Crested Francolin
- Crested Guineafowl
- Crested Kingfisher
- Crested Lark
- Crested Oropendola
- Crested Pigeon
- Crested Serpent Eagle
- Crimson-breasted Shrike
- Crimson-breasted Woodpecker
- Crimson Rosella
- Croaking Cisticola
- Crowned Eagle
- Crowned Hornbill
- Crowned Lapwing
- Curl-crested Jay
- Curlew Sandpiper