Eels, such as the one being held by a naturalist, are endangered because dams have disrupted their natural river habitat.
Chaudiere Dam could be home to one of the Ottawa River’s first eel ladders as early as next summer.
If installed, the ladder would guide endangered American eels above or around the dam, potentially allowing for their safer migration up the river.
Public consultation on the proposed ladder and other efforts by hydro companies to protect eels will begin in June.
The American eel was classified as endangered in 2007. Under the Ontario Endangered Species Act, the eel is legally protected and its habitat cannot be destroyed.
The province’s hydro facilities were initially exempt from this law and allowed to operate despite research indicating their operations killed American eels.
The exemption ends in June and companies must have an agreement in place showing their plans to protect the eels.
The eel’s endangered status is surprising given their previously huge numbers.
“Eels are a shadow of their former selves,” says John Casselman, a Queen’s University professor who studies eels. “They still exist in the system but they’re so rare.”
In the 1600s, as many as 20 million eels lived in the Ottawa River, says Casselman. Many more lived in the St. Lawrence River.
They stabilized fish communities and were a main food source for First Nations peoples. Now eels are hard to find in both water systems.
Many factors have contributed to the endangered status of the eel, says Casselman. They were heavily fished around the 1960s. River contaminants might affect reproduction and climate change alters ocean currents relied on for migration.
But perhaps most significant is the construction of large dams along the Ottawa and St. Lawrence rivers over the past 60 years.
The dams have a huge effect on eels because they are migratory fish. American eels are born in the Sargasso Sea in the North Atlantic Ocean.
Young females travel up the St. Lawrence and some enter the Ottawa River. They spend up to 20 years maturing in the fresh water and can grow a metre long and as round as an arm.
They then drift downstream to spawn in the ocean. Eels moving up or downstream are at risk of being chopped up by dam turbines.
The Ottawa is one of the most regulated rivers in Canada with more than 50 major dams along its watershed.
The St. Lawrence boasts the world’s highest ladder which transports fish over the first dam but no similar structures exist on the Ottawa River.
A 2009 study by the Community Stewardship Council of Lanark County found dead eels below the Carillon Dam about 150 kilometres east of Ottawa and the Chaudiere Dam west of Parliament Hill. These dams are the first barriers eels encounter after the St. Lawrence.
The Ministry of Natural Resources has been working with the Ontario Waterpower Association over the last year to investigate best management practices to reduce harm to eels.
A temporary ladder may be installed on the Chaudiere Dam by summer 2012 says Owen Mahaffy, director of generation for Energy Ottawa, the company that operates the dam.
The cost of the ladder plus monitoring and catch-and-release efforts would cost the company tens of thousands of dollars.
Initial placement decisions will be based on ongoing eel research on the Ottawa River.
“You can’t expect a company to spend extreme amounts of money if we don’t have good data to prove that there’s sufficient adequate numbers to justify it,” says Anne Bendig, a biologist with the Ontario Ministry of Natural Resources.
She says government has been gathering information about eels since they were classified as endangered.
With this information, hydro companies can make informed conservation decisions.
In a study last summer funded by Ontario’s Species at Risk Stewardship Fund, researchers from the Rideau Valley Conservation Authority found no eels in the Ottawa River.
But Michael Yee from the conservation authority says these results can be misleading and that anglers have reported eel sightings.
“Just because we haven’t found them doesn’t mean they aren’t there,” says Yee.
The Rideau Valley has no more funding to study eels this year, but hopes to gain further information using the efforts of volunteers. Anglers are asked to report eel sightings to the Rideau Valley authority so researchers can determine where they are living.
About 50 eels were reported in the Ottawa by anglers over the last two years.
Other methods of tracking include radio telemetry. The Arnprior Fish and Game Club began tracking eels with radio transmitters in 2008, says Kirby Punt, a Madawaska-area biologist for the Ontario Ministry of Natural Resources.
At the time, nine eels were tagged in the Lac des Chat section of the river, 30 kilometres west of Ottawa.
Two died in September when they were caught in the turbines of the Chat Falls Dam.
A third somehow made it past the dam and is now beside Chaudiere Falls in Ottawa.
“There’s no way eels should be getting around but the little buggers are still getting in,” says Punt.
The fish and game club will tag more eels this summer and continue the tracking study.
Anyone who catches or sees an eel can call 613-692-3571 ext. 1176.