Indonesian Shortfin Eel

Interesting Info

• The Indonesian Shortfin Eel is a widespread Indo-Pacific species, found from India and Southeast Asia through Indonesia and Papua New Guinea to northern Australia.
• In Australia it occurs mainly in Queensland, the Northern Territory, and northern Western Australia, where it inhabits rivers, billabongs, and estuaries.
• Its body is dark olive-brown to grey above and pale silvery underneath, with a short dorsal fin that begins behind the middle of the body — a key feature of shortfin eels.
• Like all true eels, it is catadromous, spending most of its life in freshwater before migrating to the deep tropical ocean to spawn.
• The reproductive habits of the eel are poorly understood, but it is known to spawn in the ocean before the larvae migrate to freshwater habitats.
• Indonesian Shortfin Eels are omnivorous predators, feeding on fish, prawns, snails, crabs, worms, and aquatic insects.
• They are nocturnal hunters, hiding in mud burrows, under logs, or in weedy banks by day and foraging at night.
• They can travel across damp land during rain or floods, wriggling into new waterways and even climbing low obstacles.
• Adults undertake an epic migration, leaving rivers and swimming thousands of kilometres to ocean spawning grounds believed to be in the Indonesian seas or western Pacific.
• After spawning, adults die, and the young drift back to coastal waters as tiny, leaf-shaped leptocephalus larvae.
• These larvae transform into transparent glass eels, then pigmented elvers, which swim upriver to grow into adults.
• The lifespan is usually 8–15 years, though large females may live longer before making their spawning run.