Moray Eels

Moray eels live in coral and rock holes, head poking out, mouth often open. That open-mouth pose isn't aggression — it's how they breathe (pumping water over gills). Giant morays (Gymnothorax javanicus) can reach 3 metres and are common across the Indo-Pacific.

They're not aggressive but will defend their den. Most divers see them at cleaning stations — small shrimp and wrasse pick parasites from inside their mouths. A 5-minute hover at a moray cleaning station is one of the better reef-life shows.

Andaman, Maldives, Bali, Red Sea, Komodo — present everywhere. Night dives reveal them out hunting on the reef, very different behaviour from daytime den-dwellers.