Tracking the hidden journey of eels: Why collaboration across the Indian Ocean matters

The extraordinary migrations of anguillid eels — and why saving these mysterious fish depends on collaboration across the Indian Ocean rim, comes into spotlight at the Oppenheimer Research Conference on Friday.

In a presentation titled, “Drugs, Guns and Eels: The decline of anguillid eels in East Africa and beyond”, Professor Lee Baumgartner from Charles Sturt University, Australia, will take delegates deep into the mysterious world of these extraordinary fish whose life cycle links Africa’s rivers to the far reaches of the Indian Ocean.

“Eels are one of nature’s great travellers,” Baumgartner says. “They are born in the sea, drift for thousands of kilometres as tiny larvae on ocean currents, and then enter rivers and lakes where they mature for many years before returning to the ocean to spawn.”

In a pre-conference interview, Baumgartner said these long-distance migrants are under pressure. Across the world, the combined impacts of dams, pollution, habitat loss, and climate change are blocking migration routes and disrupting river systems on which eels depend.

“In many catchments, young eels can no longer reach their nursery habitats,” Baumgartner said. “Over the past two decades, their numbers have dropped dramatically.”

Because anguillid eels cross national and continental boundaries during their life cycle, Baumgartner believes that protecting them requires coordinated regional action. “No single country can conserve this species alone,” he says. “We need an Indian Ocean rim collaboration — a partnership that brings together governments, researchers, and communities from Africa, Asia, and the Pacific.”

Eels also hold important cultural and nutritional value. For generations, they have featured in the folklore, diets, and seasonal rhythms of riverside communities. “They are a rich source of protein and part of many traditional food systems,” Baumgartner notes. “Losing them means losing both ecological and cultural heritage.”

Efforts are now underway to fill critical knowledge gaps about the species’ migration routes and breeding habits. Despite decades of research, no one has ever tracked an adult eel to its spawning ground — a mystery that continues to fascinate scientists. New tagging technologies and collaborative field studies are offering fresh hope of solving that puzzle.

Baumgartner and his team are working with partners across the Indian Ocean region to share knowledge, train early-career researchers, and support community-based conservation. “Protecting rivers, removing barriers, and reconnecting waterways will benefit not only eels but entire freshwater ecosystems,” he says.

As he will tell delegates, conserving these enigmatic creatures is about more than saving a single species. “When we safeguard eels, we also protect the health of the rivers that sustain people, wildlife, and cultures across the region.”

Jive Media Africa is the science communication partner for Oppenheimer Generations Research and Conservation (OGRC).