- Ladder-backed Woodpecker
- Lark Bunting
- Lark Sparrow
- Laughing Gull
- Lazuli Bunting
- Least Bittern
- Least Flycatcher
- Least Grebe
- Least Tern
- Lesser Goldfinch
- Lesser Scaup
- Lesser Yellowlegs
- Lincoln's Sparrow
- Little Blue Heron
- Little Gull
- Loggerhead Shrike
- Long-billed Dowitcher
- Long-eared Owl
- Long-tailed Duck
- Long-tailed Manakin
- Long-tailed Silky-flycatcher
- Long-tailed Tyrant
- Lucy's Warbler