Dusky Wrasse

Interesting Info

• The Dusky Wrasse is found in northern Australian waters including the Great Barrier Reef, Coral Sea, Timor Sea, and reefs off Western Australia.
• It has a broad Indo-Pacific distribution from the Maldives and Indonesia eastward to Fiji, Samoa and the Line Islands, north to southern Japan, and south to Australia.
• Males in their terminal phase are greenish with blue streaks on the head and darker dusky edges to the fins, while females and juveniles are more cryptic, mottled brown or olive with pale spots and streaks.
• The common name “Dusky Wrasse” refers to the darker shading seen along the margins of the fins and body of adults.
• This species forages actively during the day across reef flats, lagoons and slopes, picking food from coral rubble, algae, and sand patches.
• Its diet includes small crustaceans, worms, molluscs, tiny fishes, and microscopic shelled creatures called foraminiferans, which resemble tiny seashells under a microscope.
• When threatened or at night, it quickly buries itself in sand, a behaviour common to many wrasses and an effective defence against predators.
• Like most wrasses, the Dusky Wrasse is a protogynous hermaphrodite, beginning life as female before some transition into males. Spawning occurs in pairs, with fertilised eggs drifting in the open water.
• Although its exact lifespan is unknown, related wrasse species live for around 4–6 years in the wild.
• Predators include larger reef fishes such as groupers and snappers, which explains its reliance on burying behaviour and camouflage.
• Ecologically, the Dusky Wrasse plays a role in controlling populations of small invertebrates, while also providing food for bigger reef predators.
• Juveniles are easily confused with other small brown wrasses, making them more difficult to identify until adult features develop.