Diana’s Pigfish

Interesting Info

• Diana’s Pigfish is found in Australia from the northern Great Barrier Reef and Coral Sea (Queensland) across to north-western Western Australia, including offshore reefs such as the Rowley Shoals and Scott Reef, and at Christmas Island and Cocos (Keeling) Islands.
• Globally, it ranges across the Indo-West Pacific, from the Maldives and Sri Lanka east to Indonesia, Papua New Guinea, southern Japan, and New Caledonia.
• Juveniles are strikingly coloured: black with a broad white vertical band behind the head, a white patch on the back, and a bright red tail, making them one of the most distinctive pigfish species.
• Adults lose the bold juvenile banding and become reddish-brown with yellow to orange highlights on the fins and body.
• A key feature is the large black blotch on the upper side of the caudal peduncle (just before the tail), which is present in both juveniles and adults.
• Sexual dimorphism is subtle: males are slightly larger and develop brighter red tones than females during breeding periods.
• Like many wrasses, Diana’s Pigfish is a protogynous hermaphrodite — all start life as females, with some changing to males as they mature and gain dominance.
• Juveniles often act as cleaner fish, picking parasites from the skin of larger reef species until they transition to a benthic diet as adults.
• Adults feed mainly on small invertebrates such as molluscs, crustaceans, and worms, which they search for among rubble and sandy patches near reefs.
• It is a diurnal species, actively foraging during daylight and retreating to crevices or under ledges at night.
• Spawning occurs in pairs or small groups, with fertilised eggs released into the water column to drift until hatching.
• It likely lives for around 5–7 years, consistent with other small wrasses and pigfishes of similar size.
• Predators include larger reef fish such as groupers and snappers, especially when juveniles are out in the open cleaning bigger fish.