By Jerika Bradford
Photo: Evan Hall
American eel populations in Ontario have decreased by an alarming 90 per cent since the 1980’s, resulting in the species’ current listing as “threatened.” Eels are faced with many challenges. Climate change is warming and acidifying the ocean, water contaminants are increasing, and hydrodams are destroying their habitat and blocking their upstream migration route. It’s no wonder eels are in trouble!
They may not be cute, but eels play an important role in our aquatic ecosystem. They are a top predator in lakes and help keep other species populations in check.
What We’re Doing About It
Since 2011, CWF has been working alongside the Ontario Ministry of Natural Resources and Arnprior Fish and Game Club in the Arnprior area of the Ottawa River. We’re getting our hands dirty tracking down radio-tagged eels, which travel far upstream.
We’ve strategically set up small temporary eel ladders across Arnprior to see if juvenile eels are attempting to migrate upstream at such an early stage of development. If juvenile eels slither their way through our ladders and right into the live trap, they will then get radio tagged and released to continue on with their journey, with our researchers following close behind.
What Are the Next Steps?
Even though we’re still in the early stages of tagging, collecting and analyzing data, CWF’s Director of Conservation, Dr. David Browne, predicts that the results will confirm what he has speculated all along: juvenile eels are trying to migrate upstream but are faced with many challenges related to habitat loss, and adult eels are being killed in large numbers—as much as 40 per cent—by hydroelectric dams as they migrate downstream.
There is good news, some eels are successfully completing their migration journey unharmed! The data from this project will pinpoint the eels’ peak migration and how and where they travel. This is necessary in order to implement an effective and credible American eel recovery plan that will boost the eels’ access to their habitat. Whether this plan will involve implementing more eel-friendly turbines or shutting them down during peak migration can only be determined by further research.