- Lapland Longspur
- Laughing Dove
- Laughing Kookaburra
- Least Flycatcher
- Least Sandpiper
- Lemon Dove
- Lesser Black-backed Gull
- Lesser Flamingo
- Lesser Frigatebird
- Lesser Kestrel
- Lesser Scaup
- Lesser Short-toed Lark
- Lesser Swamp Warbler
- Lesser Whitethroat
- Lesser Yellowlegs
- Lichtenstein's Sandgrouse
- Lilac-breasted Roller
- Lincoln's Sparrow
- Little Bee-eater
- Little Bittern
- Little Black Cormorant
- Little Bunting
- Little Bustard
- Little Crake
- Little Egret
- Little Grebe
- Little Gull
- Little Owl
- Little Penguin
- Little Pied Cormorant
- Little Rock Thrush
- Little Sparrowhawk
- Little Stint
- Little Tern
- Little Wattlebird
- Long-eared Owl
- Long-tailed Duck
- Long-tailed Jaeger
- Long-tailed Tit
- Long-tailed Triller
- Long-toed Lapwing