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Napoleon (Humphead) Wrasse — illustration
AI-generated illustration for The Scuba Atlas — illustrative, not a documentary photograph.

Big Fish

Napoleon (Humphead) Wrasse

Cheilinus undulatus · Bony fish — family Labridae

IUCN: EN (decreasing) ~1.2 m total length; the largest wrasse, with old males approaching 200 kg 2–60 m depth band Well documented

Every great Indo-Pacific reef has its Napoleon, and divers learn them by name. The fish is unmistakable: a wardrobe-sized wrasse in chalkboard green scribbled with maze lines, thick lips set in permanent diplomacy, the adult's forehead hump rising like a bicorne hat. It ambles rather than swims, pausing to crunch an urchin or turn a heavy eye on the dive group — old individuals at Blue Corner or Shark Reef treat humans as familiar furniture. The species pays for that trusting bulk: prized as a luxury live-reef food fish, it has been stripped from much of Southeast Asia, and the big tame residents of protected reefs are now among its safest populations.

Respect factor: LowHarmless barring the size; historic feed-trained individuals learned to mug divers for eggs, and a nudge from 150 kg is memorable. Feeding is now banned in most parks.

Where and when to see one

"Resident" means most dives at that destination encounter them; "seasonal" means reliably present in the listed months; anything else is a bonus, not a plan.

DestinationReliabilityMonthsNotes
Sharm El Sheikh & Ras MohammedEgypt Resident — seen on most dives Year-round
PalauPalau Resident — seen on most dives Year-round
Sipadan & MabulMalaysia Resident — seen on most dives Year-round
Cairns & the Ribbon ReefsAustralia Resident — seen on most dives Year-round
North & South Malé AtollsMaldives Resident — seen on most dives Year-round

Best month, at a glance

MonthReliable destinations
January Sharm El Sheikh & Ras Mohammed · Palau · Sipadan & Mabul · Cairns & the Ribbon Reefs · North & South Malé Atolls
February Sharm El Sheikh & Ras Mohammed · Palau · Sipadan & Mabul · Cairns & the Ribbon Reefs · North & South Malé Atolls
March Sharm El Sheikh & Ras Mohammed · Palau · Sipadan & Mabul · Cairns & the Ribbon Reefs · North & South Malé Atolls
April Sharm El Sheikh & Ras Mohammed · Palau · Sipadan & Mabul · Cairns & the Ribbon Reefs · North & South Malé Atolls
May Sharm El Sheikh & Ras Mohammed · Palau · Sipadan & Mabul · Cairns & the Ribbon Reefs · North & South Malé Atolls
June Sharm El Sheikh & Ras Mohammed · Palau · Sipadan & Mabul · Cairns & the Ribbon Reefs · North & South Malé Atolls
July Sharm El Sheikh & Ras Mohammed · Palau · Sipadan & Mabul · Cairns & the Ribbon Reefs · North & South Malé Atolls
August Sharm El Sheikh & Ras Mohammed · Palau · Sipadan & Mabul · Cairns & the Ribbon Reefs · North & South Malé Atolls
September Sharm El Sheikh & Ras Mohammed · Palau · Sipadan & Mabul · Cairns & the Ribbon Reefs · North & South Malé Atolls
October Sharm El Sheikh & Ras Mohammed · Palau · Sipadan & Mabul · Cairns & the Ribbon Reefs · North & South Malé Atolls
November Sharm El Sheikh & Ras Mohammed · Palau · Sipadan & Mabul · Cairns & the Ribbon Reefs · North & South Malé Atolls
December Sharm El Sheikh & Ras Mohammed · Palau · Sipadan & Mabul · Cairns & the Ribbon Reefs · North & South Malé Atolls

Understanding them

Habitat: Outer reef slopes, channels, and lagoon passes; sleeps in caves and returns to favored ranges for decades

Range: Indo-Pacific coral reefs from the Red Sea and East Africa through Southeast Asia and Micronesia to the central Pacific

Behavior: A slow-cruising reef monarch, usually solitary, patrolling with pectoral-fin rowing strokes and an air of proprietorship. Naturally wary where fished; at protected sites like Ras Mohammed and Palau's channels, individuals become famously tame, inspecting divers eye to eye. Born mostly female, with dominant animals changing sex to male.

Diet: Mollusks, crustaceans, urchins, and toxic prey few others touch — crown-of-thorns starfish and boxfish included

Size: typically around 1.2 m; documented up to 2.0 m (total length; the largest wrasse, with old males approaching 200 kg).

How to behave around one

No feeding — it distorted behavior badly at several famous sites — no touching, and let a curious fish make the approach. Report obviously missing 'resident' Napoleons to operators; they are individually known.

Conservation

Endangered and CITES-listed; the live reef-fish trade drove collapses across Southeast Asia, and enforcement plus site protection now underpin the strongholds divers visit.

Charted sites known for them

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Sources: Wikipedia ↗IUCN Red List ↗ · Facts verified against the sources above; fields without support are labeled not yet verified.

Australia, New Zealand & East Asia

Cairns & the Ribbon ReefsNingaloo ReefCoral Sea & Osprey ReefOkinawa & the Kerama IslandsPoor Knights IslandsTownsville & the YongalaGreen IslandIzu Peninsula

Caribbean & Western Atlantic

BonaireCozumelRiviera Maya & the CenotesBelize Barrier ReefGrand CaymanIsla Mujeres & CancúnRoatánTiger Beach & Grand Bahama

Europe, Atlantic & Mediterranean

Malta & GozoSilfra & IcelandThe AzoresCanary IslandsLarnaca & the ZenobiaScapa FlowArctic NorwayMadeira

Indian Ocean & East Africa

North & South Malé AtollsAri AtollBaa Atoll & Hanifaru BayAliwal Shoal & UmkomaasMafia IslandMauritiusSeychellesSodwana Bay

Pacific Islands & Micronesia

PalauChuuk (Truk) LagoonFakaravaKona, HawaiʻiRangiroaTaveuni & Rainbow ReefBeqa Lagoon & Pacific HarbourEspiritu Santo

Red Sea & Middle East

Sharm El Sheikh & Ras MohammedBrothers, Daedalus & St John'sDahabHurghada & El GounaMarsa Alam & the Deep SouthAqabaDaymaniyat IslandsMusandam Peninsula

Southeast Asia & Coral Triangle

Bali & Nusa PenidaKomodoRaja AmpatSipadan & MabulAnilaoCoronKoh TaoLembeh Strait

The Americas & Eastern Pacific

Galápagos IslandsCocos IslandFlorida KeysSea of Cortez & Cabo PulmoSocorro & the RevillagigedosBritish ColumbiaCalifornia Channel IslandsCosta Rica Pacific Coast