21 Mai 2012
The Humphead “Napoleon” wrasse (Cheilinus undulatus) is a real mastodon. It is the largest wrasse ever seen in the world. Commonly referred as the Mara in the Maori language, the humphead wrasse can measure 6.6ft and 440lbs.
This giant is recognizable by its thick lips, a round tail and its extremely movable eyes. During its growth, its scales can change colour depending on its age and its environment. The mature specimens develop a frontal hump, a characteristic that gives the name to this species.
It can be observed generally near the oceanic slopes. The Pacific Ocean, the Indian Ocean and the Red Sea are geographical habitats where we can see the Napoleon wrasse. It has been noted that the density of Napoleon wrasse population in an area is an indication of a reef’s health - the higher the density, the healthier the coral reef.
Seemingly territorial, the “Napoleon” as it is fondly referred to, chooses a reef cavity where it settles throughout its lifespan. Documented as a rather solitary fish, the Napoleon wrasse has been observed within a colony of one male specie with a real “harem” of females.
Its diet is made up of fish, molluscs, crustaceans and urchins. It is an surprisingly agile hunter thank to its powerful mouth suction movement when it engulfs its prey. Its protractible jaw (that can be projected forward) and a strong vacuum suction motion allows it to capture prey at a distance. An outstanding hunter, seemingly docile, it can be as quick as lightning.
Like other grouper species, the Napoleon wrasse is an hermaphrodite. They are born female and become male a year later. Each wrasse becomes sexually mature at 5 years old.
The Napoleon wrasse is far from shy which makes it quite approachable to divers. A very curious fish, its curiosity sometimes endangers to its predators: humans and sharks.
An imposing creature in its natural environment, and completely harmless, you will have the chance of encountering the Napoleon wrasse around islands of Tuamotu archipelago.
© Photos S.Girardot