Clown anemonefish

Photo: Vinh Le · CC BY-NC

The clown anemonefish lives exclusively among the tentacles of host anemones, protected by a mucus coat that prevents stinging. At Anemone Reef the density is unusually high: every large Heteractis magnifica anemone holds a breeding pair plus juveniles. The relationship is mutualistic — the fish aerates and fertilises the anemone while gaining shelter and food.