Muscling in on mussel habitat: North America’s most endangered species

A silent crash is taking place in Canada’s waters and around the world. Globally, freshwater species have declined 76 percent over the last four decades. And here at home, freshwater life is dropping at an alarming rate.
That’s why during Canada Water Week, we want to celebrate one of our most important, and the most endangered group of freshwater species in North America – the freshwater mussel. More than half of the continent’s freshwater mussels are in danger of going extinct.

Freshwater mussels on a lake bottom, North America. © Eric Engbretson Underwater Photography / WWF-Canada

Why should we care?

Mussels are filter feeders, which means this invertebrate species actually works as nature’s Brita filter to help keep our water clean. Take the round hickorynut mussel: it filters up to 40 litres of water a day! So if that water is polluted, this species absorbs those toxic chemicals – while at the same time keeping our waterways clean and healthy.
Mussels are also important because they are food for a wide array of other wildlife like fishes, otters, mink, muskrats and birds. If mussels are lost, the whole ecosystem will suffer.
Freshwater mussels are molluscs – soft-bodied animals without a skeleton (invertebrates) that live on the bottom of streams, rivers, lakes and ponds. The maximum life span of a mussel is believed to be 18 years. But some, like the Rocky Mountain Ridged mussel, are estimated to live up to 30 years.

If freshwater mussels are so important then why are their populations in so much trouble in Canada and around the world? And why aren’t we doing more to protect them?

There are many different species of mussels from Mapleleaf mussels, rainbow mussels to salamander mussels, which are all facing serious threats.
As urban expansion continues at a rapid rate, mussels face many threats. Increasing sediment in the water from agriculture can bury, smother and starve this filter-feeding species. Exposure to agricultural chemicals and water run-off from roads are also potential threats. The zebra mussel is one of Canada’s most notorious invasive species, and out-competes Canada’s native freshwater mussels for habitat and food in areas where zebra mussels are now established.

WWF staff members volunteer on a freshwater mussel recovery project in the Ausable River in Ontario. © WWF-Canada

What can you do to help protect them?

We need to be very careful about what we put into our water. That includes everything from road salt to household cleaning products. Everything we can do to make our waters more healthy helps – because what affects mussels will ultimately affect us.
Mussels are a critical component of the freshwater food chain. They provide us with healthy and clean waters. So during Canada Water Week, let’s remember – it’s up to us to celebrate and help protect them!
During Canada Water Week, show your support for our rivers, lakes and streams. Join the hundreds of Canadians working across the country to protect water health. You, too, can become a Water Hero by making a donation to our Loblaw Water Fund projects.