- Magellanic Oystercatcher
- Magellanic Penguin
- Magnificent Frigatebird
- Malagasy Turtle Dove
- Mallard
- Mandarin Duck
- Mangrove Hummingbird
- Mangrove Swallow
- Mangrove Warbler
- Marsh Tit
- Marsh Warbler
- Masked Booby
- Mauritius Fody
- Mauritius Grey White-eye
- Mauritius Olive White-eye
- Mealy Amazon
- Melanesian Flycatcher
- Melodious Blackbird
- Metallic Pigeon
- Mexican Violetear
- Middle Spotted Woodpecker
- Monk Parakeet
- Morelet's Seedeater
- Mourning Sierra Finch
- Muscovy Duck
- Mute Swan