- Large-billed Gerygone
- Large-billed Tern
- Lark Sparrow
- Laughing Dove
- Laughing Falcon
- Laughing Gull
- Laughing Kookaburra
- Leaden Flycatcher
- Least Bittern
- Least Grebe
- Least Sandpiper
- Least Tern
- Lemon-bellied Flyrobin
- Lemon-chested Greenlet
- Lesser Crested Tern
- Lesser Frigatebird
- Lesser Goldfinch
- Lesser Kiskadee
- Lesser Sand Plover
- Lesser Yellow-headed Vulture
- Lesser Yellowlegs
- Lesson's Seedeater
- Lettered Aracari
- Limpkin
- Lineated Woodpecker
- Lined Forest Falcon
- Lined Seedeater
- Little Black Cormorant
- Little Blue Heron
- Little Bronze Cuckoo
- Little Chachalaca
- Little Corella
- Little Cuckoo
- Little Eagle
- Little Egret
- Little Friarbird
- Little Penguin
- Little Pied Cormorant
- Little Shrikethrush
- Little Tern
- Little Wattlebird
- Little Woodpecker
- Little Woodswallow
- Loggerhead Shrike
- Long-billed Corella
- Long-billed Curlew
- Long-tailed Finch
- Long-tailed Hermit
- Long-tailed Potoo
- Long-tailed Tyrant
- Long-winged Harrier