| Common Name | Scientific name |
|---|---|
| Sociable Lapwing | Vanellus gregarius |
| Social Flycatcher | Myiozetetes similis |
| Socorro Dove | Zenaida graysoni |
| Socorro Mockingbird | Mimus graysoni |
| Socorro Wren | Troglodytes sissonii |
| Soft-plumaged Petrel | Pterodroma mollis |
| Solitary Eagle | Buteogallus solitarius |
| Solitary Sandpiper | Tringa solitaria |
| Solitary Snipe | Gallinago solitaria |
| Song Sparrow | Melospiza melodia |
| Song Thrush | Turdus philomelos |
| Song Wren | Cyphorhinus phaeocephalus |
| Sooty Grouse | Dendragapus fuliginosus |
| Sooty Shearwater | Ardenna grisea |
| Sooty Shearwater | Puffinus griseus |
| Sooty Tern | Onychoprion fuscatus |
| Sooty Thrush | Turdus nigrescens |
| Sooty-capped Chlorospingus | Chlorospingus pileatus |
| Sooty-faced Finch | Arremon crassirostris |
| Sooty-headed Bulbul | Pycnonotus aurigaster |
| Sooty-headed Tyrannulet | Phyllomyias griseiceps |
| Sooty-headed Wren | Pheugopedius spadix |
| Sora | Porzana carolina |
| South African Shelduck | Tadorna cana |
| South Polar Skua | Stercorarius maccormicki |
RingBase adheres to EURING codes.
