They go by names like Lilliput, Rainbow, Pigtoe, and Snuffbox, and despite being perpetually mistaken for rocks, they’re of vital importance to Ontario’s rivers and streams.

These species of freshwater mussels are among 14 at risk in Ontario. Federal laws protect at-risk mussel populations by requiring that they be moved upstream before construction begins on new infrastructure projects like bridges and roads that disturb their habitats. Armed with a new $270,000 grant, UWindsor researcher Catherine Febria is studying whether mussel populations ever rebound after such translocations.

“No one has ever gone back to these sites to make sure these species have survived,” said Dr. Febria, an assistant professor of integrative biology and co-director of the Great Lakes Institute for Environmental Research organic analysis and nutrients lab. “There is zero published data on how successful these translocations are. That’s why this is an incredible research opportunity.”

Febria’s grant comes from Mitacs, a national not-for-profit organization that creates partnerships among Canadian academia, private industry, and government to provide research and training opportunities. It is linked to the replacement of the Argyle Street Bridge in Caledonia that spans the Grand River. The contractor, Dufferin Construction, a division of CRH Canada Group Inc., has hired an environmental consultant to translocate the species at risk and enlisted Febria and her Healthy Headwaters Lab to conduct research on their recovery.

Environmental laws require contractors to provide reports on species at risk that include how their populations are faring in the months following translocation. But Febria and her research team, who prepared a manuscript looking at more than 1,000 published studies on freshwater mussel restoration, know mussel populations don’t rebound in a year. Because environmental laws don’t require it, no one has ever returned to these sites in subsequent years to see if mussels have ever recovered.

“We have engaged government agencies and on-the-ground practitioners to accessing existing datasets on translocations conducted over the past decade or longer,” Febria said. She said her team will survey older construction projects across Ontario to assess whether translocations are an effective conservation strategy.

“Our goal in doing this is to inform better practices were species at risk are concerned.”

Mussels are important to aquatic habitats. They consume bacteria and algae, improving water quality for other aquatic species. Their larvae attach themselves to the gills of fish. They use the fish’s movement to draw in nutrients from the water. When they are mature enough, they drop off and live out their days in the sediment where they are, at first glance, indistinguishable from rocks.

Since their populations are inextricably intertwined to fish species, mussels are a good indicator of the health of commercial and sports fisheries, Febria explained.

There are 41 species of freshwater mussels in Ontario, many with names straight out of a Harry Potter novel. The Purple Wartyback has a bumpy shell. The Fawnsfoot looks as if a tiny, magical creature traipsed across its shell leaving behind rows of footprints.

The Mapleleaf, a species of special concern, looks like it could adorn the Canadian flag.

Some mussels are small and look like stones, Febria said. “Some are the size of my face.”  

Mussel shells were a resource prized by the Canada’s button industry. The interiors of the shells, in iridescent whites, pinks, browns, and greys, were cut into discs and marketed as mother-of-pearl buttons to clothing manufacturers in Europe.

The tradition of using mussel shells for buttons was borrowed from Indigenous people who had long been using them to create intricate designs on blankets and clothing.

Indigenous people also held the knowledge that freshwater mussels are not edible. Because a single mussel can filter 40 litres of water each day, toxins accumulate in their tissue. People who have tried to eat them say they taste like latex.

“This is why local knowledge is so important,” said Febria. She makes it her practice to engage Indigenous rights holders in her research everywhere she has worked around the globe.

Febria holds a Tier 2 Canada Research Chair in Freshwater Restoration Ecology, part of a federal initiative to fund academics who hold the promise of making Canada a global leader in research and development.

The Grand River project dovetails with work she is already doing on mussel species in the Sydenham River watershed. That work is possible with a four-year grant for $1.6 million from the Canada Nature Fund.

Her Mitacs grant will fund two students, one technician, and research costs for two years.

—Sarah Sacheli