- Maghreb Magpie
- Maghreb Wheatear
- Magnificent Bird-of-paradise
- Magnificent Frigatebird
- Malabar Pied Hornbill
- Malachite Kingfisher
- Mallard
- Mandarin Duck
- Mangrove Swallow
- Many-banded Aracari
- Many-spotted Hummingbird
- Marail Guan
- Marbled Duck
- Marbled Frogmouth
- Marsh Sandpiper
- Marsh Tit
- Masked Crimson Tanager
- Masked Flowerpiercer
- Masked Tityra
- Masked Trogon
- Masked Water Tyrant
- Meadow Pipit
- Mealy Amazon
- Mediterranean Gull
- Medium Egret
- Melodious Blackbird
- Melodious Warbler
- Metallic Starling
- Mexican Violetear
- Middle Spotted Woodpecker
- Mistle Thrush
- Monk Parakeet
- Montagu's Harrier
- Montane Woodcreeper
- Montezuma Oropendola
- Mottled Owl
- Mountain Cacique
- Mountain Owlet-nightjar
- Mountain Thrush
- Mountain Wren
- Mourning Dove
- Moussier's Redstart
- Moustached Puffbird
- Moustached Treeswift
- Mrs. Gould's Sunbird
- Muscovy Duck
- Mute Swan
- Myrtle Warbler