The Hidden Story Behind Lake Huron’s Crystal-Clear Waters: Part One

by Bob Montgomery

The clear water in Lake Huron would lead us to believe the lake is very healthy.

But the Executive Director of the Lake Huron Coastal Centre says the clear water doesn't tell the whole story. Alyssa Bourassa says the invasive quagga and zebra mussels tell a different story. Quagga mussels are small, striped mussels that originate in Eastern Europe. They crossed the ocean by hanging onto ships and found their way into the Great Lakes. Once they're here they spread rapidly and began to change the ecosystem, one mussel at a time. Quagga and zebra mussels are both filter feeders, meaning they suck in water and filter out tiny particles of food. While this might sound harmless, or even beneficial, there’s a catch: they’re incredibly efficient at it. So much so, that they’re filtering out nearly all the tiny plants and animals known as plankton that other species rely on for food.

The quagga mussels have become a bigger problem as their population increases. They have now out competed their zebra mussel cousins to become the most common mussel in the Great Lakes. While zebra mussels usually hang out in shallow waters, 2 to 12 meters deep, quagga mussels prefer the deep, calm, and cool waters, going as far down as 100 meters, taking over these deeper waters, making it harder for native species to thrive. The quagga’s ability to dominate and adapt has helped them take over and they now filter more water than zebra mussels, simply because their population is much greater. The quagga mussels are causing significant changes in Lake Huron’s ecosystem, and it's a clear reminder of how resilient and adaptable these invasive species can be.

Stay tuned for part two in early February to learn about the future of invasive mussels and what can be done to protect Lake Huron.

Photos courtesy of the Lake Huron Centre for Coastal Conservation