- Maccoa Duck
- Madeira Chaffinch
- Madeira Firecrest
- Magnificent Bird-of-paradise
- Magnificent Frigatebird
- Magnificent Riflebird
- Magnolia Warbler
- Magpie Tanager
- Malabar Pied Hornbill
- Malabar Trogon
- Malachite Kingfisher
- Malachite Sunbird
- Malaysian Pied Fantail
- Mallard
- Maned Duck
- Mangrove Sunbird
- Mangrove Swallow
- Mangrove Warbler
- Many-banded Aracari
- Many-spotted Hummingbird
- Many-striped Canastero
- Marabou Stork
- Marbled Duck
- Marsh Sandpiper
- Marsh Tit
- Marsh Warbler
- Martial Eagle
- Masked Booby
- Masked Bowerbird
- Masked Crimson Tanager
- Masked Flowerpiercer
- Masked Tityra
- Masked Trogon
- Masked Water Tyrant
- Meadow Pipit
- Mealy Amazon
- Mediterranean Gull
- Melancholy Woodpecker
- Melodious Blackbird
- Melodious Warbler
- Merlin
- Mexican Sheartail
- Mexican Violetear
- Middle Spotted Woodpecker
- Mistle Thrush
- Moluccan Eclectus
- Mongolian Finch
- Monk Parakeet
- Montane Foliage-gleaner
- Montane Woodcreeper
- Montezuma Oropendola
- Morelet's Seedeater
- Mountain Elaenia
- Mountain Owlet-nightjar
- Mountain Peltops
- Mountain Wheatear
- Mountain Wren
- Mourning Collared Dove
- Mourning Dove
- Moustached Antpitta
- Moustached Treeswift
- Muscovy Duck
- Musician Wren
- Mute Swan
- Myrtle Warbler