- Having a yellow tail.
- A fish native to the northwest Pacific, often used in sushi, the Japanese amberjack, Seriola quinqueradiata.
- yellowtail flounder, Limanda ferruginea.
- yellowtail horse mackerel, Trachurus novaezelandiae.
- The yellow-tailed oriole, a passerine bird in the New World family Icteridae.
- yellowtail amberjack, Seriola lalandi.
- Atlantic bumper, Chloroscombrus chrysurus.
- whitespotted devil, Plectroglyphidodon lacrymatus
- The yellow-tailed black cockatoo, a large cockatoo native to the south-east of Australia.
- Any of various fish with yellow tails, including:
- yellowtail snapper, Ocyurus chrysurus.
- A European moth
- The yellow-tailed woolly monkey, a New World primate endemic to Peru.