2,000 kilometres of slippery business in the Macleay River NSW
Not everyone would be thrilled to see thousands of eels swimming their way, but we recently received an intriguing video from David Faircloth, showcasing a remarkable mass migration of Long-finned eels.
David is an OzFish member and an executive of the Coffs Harbour Chapter and was lucky enough to capture the eels migrating towards the upper reaches of the Macleay River, west of Kempsey NSW, after a 2,000 km journey.
The mass migration event is a sight to see, with the video below perfectly capturing the frantic movement of the 80-150 mm young eels to their preferred freshwater habitat.
The epic journey: breeding and migration
Long-finned eels (Anguilla reinhardtii) have an extraordinary life cycle. Born in the deep ocean waters near New Caledonia, these eels embark on a monumental journey to the freshwater rivers and streams of eastern Australia.
They then spend most of their lives, up to several decades, in these freshwater habitats. Once they reach maturity, they undertake a one-way migration back to their oceanic spawning grounds to reproduce and subsequently die. The developing larvae then drift on ocean currents for about a year, before returning to Australian streams to continue the cycle.
Right place, right time
David was checking the rising conditions in the Macleay River, around 100 km from the Kempsey coast, when he noticed thousands of juvenile eels, with birds of prey also watching from the bank.
“It was an impressive sight and thankfully I had my camera to capture the moment; it lasted for around 20 minutes”.
“At one point, they were wriggling over my submerged feet and would even hide behind my hands for a break from the strong current.”
“You’d be amazed at how far they’ve travelled. All the way from the Coral Sea, over 2,000 km away- yet they still battle the river flow to reach their preferred habitat in the headwaters.” David believes the mass migration was likely triggered by increased river flows from heavy rains, which signal to the eels that it’s safe to reach the headwaters without getting stranded.
Ecological significance
Long-finned eels play a crucial role in aquatic ecosystems. As opportunistic predators, they help maintain the balance of species populations by preying on fish, crustaceans, and other small animals. Their presence indicates a healthy water system, where they serve as both predator and prey, contributing to the biodiversity and stability of their habitats.
Conservation and protection
Despite their resilience, Long-finned eels face several threats. Habitat destruction, water pollution, and barriers to migration such as dams and weirs. OzFish and our team of volunteers, like David, have worked along many waterways Long-finned eels call home, ensuring they have access to suitable habitat and migration routes.
Join OzFish here, to support our habitat restoration projects.
Fun fact
Did you know that Long-finned eels can traverse overland? They can move across wet grass or damp terrain, especially during rainy nights, to reach new habitats or continue their migration.
The video shared by David not only highlights the incredible journey of Long-finned eels but also underscores the importance of preserving the natural processes that allow such migrations to occur. By understanding and protecting these unique creatures, we contribute to the health and diversity of our aquatic ecosystems.