Three hickorynut mussels collected in the Ottawa River.
If you enjoyed fishing, swimming and boating in the Ottawa River this summer, you have mussels to thank for keeping the water clean, according to Canadian Museum of Nature research scientist André Martel. And that’s why he’s studying these natural water filters, including the rare and endangered hickorynut mussel, in hopes of protecting them for future generations.
So far, Martel’s ongoing research, which is usually funded and published by the museum, has revealed a high diversity of mussels in the Ottawa River. The river is home to 16 of the 55 freshwater mussel species found in Canada, about 30 per cent of the full range of types.
Martel says this is a sign of good health.
“The presence of mussels usually indicates low pollution and good water chemistry because they are filter feeders and their life cycle depends on it,” he says. “Based on what we’ve found, the river isn’t as bad as you think.”
And something special has to be happening for the mysterious hickorynut mussel to make its home there. The brown, nut-shaped mussel is found in only six other rivers in Canada.
Martel is searching for reasons why the endangered mussel, which often lives up to 20 years, is present in the Ottawa River and so few others.
In the first stage of its life, the hickorynut attaches to the gills of sturgeons to absorb nutrients and move around. When it’s ready, it drops off onto a sandy bed, where it spends the remainder of its life.
But Martel’s research shows the hickorynut survives only where sturgeons thrive. It‘s never associated with other types of fish, so the hickorynut population appears to depend on the abundance of sturgeons.
Otawa Riverkeeper Meredith Brown said the first step to helping the hickorynut is finding out more about it. Then the goal of protecting the river’s endangered species can be accomplished.
“Wouldn’t it be great if the Ottawa River in the future is home to species you can’t find anywhere else?” she says. “To me it would indicate we’re being good stewards in our river.”