Oxleyan Pygmy Perch

Interesting Info

• The Oxleyan Pygmy Perch is one of Australia’s rarest freshwater fish, found only in a tiny stretch of coastal wetlands in northern New South Wales and southern Queensland.
• Their bodies are olive to golden-brown, often with darker blotches, and males become brighter and more colourful during the breeding season.
• They are habitat specialists, living in acidic, tannin-stained swamps, creeks, and lakes with dense aquatic plants, often surrounded by paperbark and wallum heathland.
• These waters are usually soft, dark, and low in nutrients, making them a very challenging environment that only a few species can tolerate.
• Young fish feed on tiny plankton and insect larvae, while adults eat a wider mix of aquatic insects, small crustaceans, and worms.
• The entire distribution of this fish is limited to fewer than 20 known locations, making them extremely vulnerable to habitat changes.
• Breeding occurs in spring and summer when males defend small territories among aquatic plants. Females lay sticky eggs on vegetation, and hatchlings stay hidden in weedy cover.
• They are considered a “flagship species” for wallum wetlands — if Oxleyan Pygmy Perch are present, the ecosystem is healthy.
• Threats include habitat clearing, water pollution, invasive fish (like Gambusia), drought, and climate change, all of which shrink their already small habitat.
• Lifespan is short, usually 2–3 years, though in cool, stable habitats some may live a little longer.