siskin, red - spinetail, slaty
- siskin, red
- siskin, Rüppell’s
- siskin, saffron
- siskin, Symon’s Cape
- siskin, thick-billed
- siskin, Tibetan
- siskin, Yarrell’s
- siskin, yellow-bellied
- siskin, yellow-faced
- siskin, yellow-rumped
- sitella
- sitella, Australian
- sitella, orange-winged
- sitella, Papuan
- sitella, pink-faced
- sitella, varied
- siva
- siva, bar-throated
- siva, blue-winged
- siva, stripe-throated
- skimmer
- skimmer, African
- skimmer, black
- skimmer, Indian
- skimmers
- skua
- skua, Arctic
- skua, Buffon’s
- skua, great
- skua, long-tailed
- skua, MacCormick’s
- skua, pomarine
- skua, south polar
- skuas
- smew
- smoker, murray
- snipe
- snipe, African
- snipe, Auckland
- snipe, banded
