An Overview

It’s no secret that Zebra Mussels have invaded Lake Minnetonka, but what exactly are the effects that these small filter feeders have on the lake? To start, Zebra Mussels are an invasive species from the Eastern Europe and Western Russia area, and because of this, have no natural predators to manage their population. When you add in the fact that they begin reproducing at 2 years old, live up to 5 years, and an individual female can release up to 1 million eggs every single year, this small invasive species becomes a big problem.

How they harm our lakes

With somewhere between 20,000-30,000 Zebra Mussels in one square meter and the ability of an individual mussel to filter up to one liter of water per day, Zebra Mussels have a few major effects on our lakes. The first effect is how they affect fish and other aquatic species. Because they filter so much water, they are effectively taking needed nutrients away from the native species in Lake Minnetonka.

Another impact these little guys are having on the lake is the massive change in where lake weeds can grow. You may think that by filtering all that water, Zebra Mussels would be depriving lake weeds of the nutrients they need to grow. The reality is quite the opposite. Just like land plants, lake plants get their energy from the sunlight that penetrates the water. This is where Zebra Mussels come into play. By filtering so much water, Zebra Mussels are increasing the water clarity and causing sunlight to reach deeper and deeper depths.

Lasting effects

The result? In the last decade, the depth at which weeds on Lake Minnetonka are able to grow has increased from 10-12 feet to 16-18 feet in the past decade. As of right now we cannot fully reverse the effects of the rapidly expanding Zebra Mussels, however, we can stop them from spreading. To learn more about Zebra Mussel and how to stop them from spreading we have attached a few sources for you!

https://nas.er.usgs.gov/queries/FactSheet.aspx?speciesID=5

https://www.extension.umn.edu/environment/water/features/zebra-mussels-and-you/index.html

https://www.dnr.state.mn.us/invasives/aquaticanimals/zebramussel/index.html

https://www.minnehahacreek.org/project/usgs-zebra-mussel-zequanox-study