- Macleay's Honeyeater
- Madagascar Blue Pigeon
- Madagascar Buzzard
- Madagascar Cuckoo
- Madagascar Grebe
- Madagascar Harrier-Hawk
- Madagascar Hoopoe
- Madagascar Ibis
- Madagascar Lark
- Madagascar Magpie-Robin
- Madagascar Nightjar
- Madagascar Owl
- Madagascar Plover
- Madagascar Swamp Warbler
- Madagascar Wagtail
- Madeira Firecrest
- Magellanic Penguin
- Magellanic Snipe
- Magenta-throated Woodstar
- Magnificent Frigatebird
- Magpie-lark
- Magpie Goose
- Magpie Shrike
- Magpie Tanager
- Maguari Stork
- Malabar Pied Hornbill
- Malachite Kingfisher
- Malachite Kingfisher (thomensis)
- Malagasy Bulbul
- Malagasy Coucal
- Malagasy Green Sunbird
- Malagasy Kingfisher
- Malagasy Pond Heron
- Malagasy Turtle Dove
- Malagasy White-eye
- Malaysian Pied Fantail
- Mallard
- Mandarin Duck
- Maned Duck
- Mangrove Cuckoo
- Mangrove Rail
- Mangrove Robin
- Mangrove Swallow
- Mangrove Warbler
- Mangrove Whistler
- Many-colored Rush Tyrant
- Marabou Stork
- Marbled Godwit
- Marico Flycatcher
- Maroon-bellied Parakeet
- Marsh Tit
- Marsh Warbler
- Martial Eagle
- Martinique Oriole
- Mascarene Martin
- Masked Duck
- Masked Flowerpiercer
- Masked Gnatcatcher
- Masked Lapwing
- Masked Tityra
- Masked Trogon
- Masked Water Tyrant
- Maui Alauahio
- Mauritius Bulbul
- Mauritius Fody
- Mauritius Grey White-eye
- Mauritius Kestrel
- Meadow Pipit
- Mealy Amazon
- Mediterranean Gull
- Medium Egret
- Medium Ground Finch
- Melanesian Flycatcher
- Melodious Blackbird
- Melodious Warbler
- Merlin
- Meves's Starling
- Mexican Cacique
- Mexican Violetear
- Meyer's Parrot
- Middle Spotted Woodpecker
- Mistletoebird
- Monk Parakeet
- Montagu's Harrier
- Montane Woodcreeper
- Montezuma Oropendola
- Moss-backed Tanager
- Mottled Duck
- Mottled Owl
- Mountain Bulbul
- Mountain Caracara
- Mountain Chickadee
- Mountain Wheatear
- Mourning Collared Dove
- Mourning Dove
- Mourning Sierra Finch
- Mourning Wheatear
- Moussier's Redstart
- Mulga Parrot
- Mute Swan
- Myrtle Warbler