According to the Indiana Department of Natural Resources, Zebra Mussels have gradually become a problem species in Geist Reservoir. Their presence was first noted at Geist Lake around 2011, and issues related to invasive species have continued to pop up over the past decade. 

The presence of zebra mussels can cause a wide range of ecological, recreational, and economic concerns. Did we mention they are nearly impossible to eradicate? Not ideal. Keep reading to learn more about invasive zebra mussels and how we can all work together to understand them at Geist Reservoir!

Understanding the Adverse Effects of Zebra Mussels

Zebra mussels are small freshwater mollusks that are native to Eastern Europe/Western Asia. They were first discovered in Canada in 1988 and are said to have been brought over via freighters traveling from Europe to the Great Lakes. With mature female zebra mussels having the capacity to release up to 1 million eggs each year, it’s no surprise that they were able to quickly spread and make their journey to other waterways—including those in Indiana!

Two to three weeks after they are born, zebra mussels grow root-like threads of protein called “byssal threads” that allow them to firmly adhere to virtually any surface. Zebra mussels have been known to attach themselves to PVC, plastic, metal, stone, concrete, wood, steel, aluminum, fiberglass—even on crayfish, other mussels, and softer substrates like plants!

This rapid ability to reproduce and effectively take over results in adverse long-term impacts. Here are a few adverse effects zebra mussels can have on a body of water like Geist Reservoir: 

  • Zebra mussels’ resilience and rapid colonization rate make them incredibly difficult to control. 
  • Zebra mussels may increase the likelihood of toxic blue-green algae blooms and higher toxins in fish populations.
  • Raw water intakes for drinking water can become blocked with zebra mussels.
  • Swimming and recreational areas may be impacted by the sharp shells of zebra mussels, which can result in cuts or other injuries to lake-goers. 
  • The inevitable death and decomposition of zebra mussels can create extremely foul odors.
  • Zebra mussels can cause extensive boat hull and motor damage, as well as increase drag and reduce speed. This results in increased fuel consumption for motorized boats.

Working Together to Control the Spread of Zebra Mussels

As stated previously, once a population of zebra mussels has become established, it’s nearly impossible to eradicate them. To get rid of them completely, you’d also have to destroy everything else that also lives in the water with them.

Since we don’t find a wipe-out of the Geist Lake ecosystem a viable option, we think the next best means of control is to educate boaters on what they can do to ensure they aren’t contributing to the spread. While we understand that managing the spread of zebra mussels may sound daunting, we must work together to prevent worse proliferation in the future.

Here are a few simple actions boaters can take to prevent the spread of aquatic invasive species like zebra mussels:

  • Remove all plant life, mud, etc., from your boat and place them in the trash.
  • Drain your bilge, live wells, bait buckets, water lines, engine, and boat trailers at access ramps to prevent the transport of invasive species to other waters.
  • Let equipment dry in the sun for five days after a boating trip. This will prevent the spread of both adult zebra mussels and their larvae.
  • If the 5-day timeframe does not work for your boating schedule, you can effectively disinfect your boat and equipment with a solution of water and 5% bleach.
  • When cleaning your boat and equipment—do not allow the potentially contaminated water to empty into any nearby storm sewer or body of water.

Help Us #SaveGeist!

We have been taking on projects like organizing regular trash pick-up, mitigating sediment loads, and developing/implementing a lake treatment program for nearly two decades. In the last ten years or so, issues have started to arise with the increase of aquatic weeds, algae blooms, and zebra mussels—and we’re here to educate our community and provide them with the steps to preserving Geist Lake. 

Learn more about how you can help preserve our great community asset by supporting our mission to #SaveGeist.