Napoleon Wrasse

1. Named for a French Emperor's Hat

The common name "Napoleon" comes from the adult male's prominent forehead bump, which divers thought resembled Napoleon Bonaparte's bicorne hat. In Australia and the Pacific it's often called Māori wrasse; in Hong Kong live-fish markets it was simply "so mei" (苏眉)—a name that became synonymous with luxury dining and overfishing.

2. Largest Wrasse on Earth

Cheilinus undulatus is the biggest species in family Labridae. Males can reach 2.3 m standard length and weigh up to 191 kg—roughly the mass of a large adult human. On a reef full of anthias and butterflyfish, a Napoleon sliding past feels like a truck entering a parking lot.

3. Protogynous Hermaphrodite

All individuals begin life as females. As they grow—often over decades—some transition into terminal-phase males with larger size, bolder color, and the signature forehead hump. This life-history strategy means removing large males from a population disrupts breeding structure for years.

4. Crown-of-Thorns Predator

Napoleons are one of the few reef fish known to eat crown-of-thorns starfish (Acanthaster spp.), a coral-eating pest. They also tackle toxic prey like boxfish and sea hares, using powerful pharyngeal teeth to crush shells and spines. Lose the Napoleons and you lose a natural biocontrol agent.

5. Site-Faithful Homebodies

Adults occupy limited home ranges and patrol the same reef sections day after day. Experienced dive guides at sites like Blue Corner (Palau) or Ras Mohammed know individual fish by face markings. You seldom see more than a handful on a single reef—density was never high, which makes current scarcity worse.

6. Slow Life, Slow Recovery

Napoleon wrasse can live 30+ years and mature late. They spawn in distinct pairs, releasing eggs into the water column. Low reproductive output plus heavy fishing pressure is why IUCN upgraded them from Vulnerable to Endangered—recovery takes generations, not seasons.

7. CITES and the Live Reef Fish Trade

Listed on CITES Appendix II since 2004, international trade requires permits. Yet the live reef fish trade—especially to Hong Kong and southern China banquet markets—drove catastrophic declines across Southeast Asia. A single large male could fetch thousands of dollars alive in a restaurant tank.

8. Curious but Not Harmless to Approach

Wild Napoleons are famously inquisitive and may swim directly toward divers—thrilling for photographers, dangerous if you interpret curiosity as an invitation to touch or feed. Hand-feeding at tourist sites has created habituated, aggressive individuals and is illegal in most range countries.

9. Juveniles Hide in Coral Thickets

Young fish are reddish-orange and shelter in branching staghorn Acropora and soft-coral gardens, sometimes in seagrass beds. You rarely see juveniles on typical wall dives—they're a macro-habitat specialty until they outgrow the nursery and move to outer reef slopes.

10. A Barometer of Reef Health

Where Napoleons persist in numbers, you are usually looking at a reef with intact outer-slope habitat, enforcement against blast fishing, and some protection from the live-fish trade. Their absence from a site that should have them is a red flag—either the fish were stripped out or the habitat was wrecked first.