WAbbott's booby
WʻAkiapolaʻau
WAldabra drongo
WAttwater's prairie chicken
WAuckland rail
WBertram's weaver
WBishop's ʻōʻō
WBlack mamo
WBlack-browed greenbul
WBlack-winged petrel
WBlue-winged racket-tail
WBuller's albatross
WChatham petrel
WChatham shag
WChestnut owlet
WCochabamba mountain finch
WLaysan albatross
WMascarene teal
WMaui ʻakepa
WMaui Nui ʻakialoa
WMaui parrotbill
WMauritius night heron
WMauritius owl
WMauritius sheldgoose
WOlive-flanked ground robin
WPale martin
WPringle's puffback
WPuaiohi
WPurple-breasted sunbird
WRegal sunbird
WSalvin's albatross
WSharpe's rail
WSjöstedt's greenbul
WSnares snipe
WSouth polar skua
WSpeckle-breasted woodpecker
WSpot-fronted swift
WStripe-breasted tit
WStuhlmann's starling
WStyan's bulbul
WSulawesi bush warbler
WTolima blossomcrown
WViolet-throated metaltail
WWhite-bellied tyrannulet
WWhyte's barbet
WYellow-capped weaver
WYellow-throated apalis