Future Elementary Science Educators: Zebra Mussels Strike Back!

By: Eunice Jang, McKenzie Palchak, Matt Kujala, and Stella Rodriguez

An invasive species that multiply by the millions every year, the zebra mussel should not be overlooked. These freshwater mussels have impacted the Great Lakes of Michigan in different ways and this blog will hopefully give more insight to what zebra mussels are, their economic and ecologic effects to the Michigan community, prevention of the spread of zebra mussels, and lesson plans for teachers. This blog is a great resource for elementary educators as the links down below will be categorized for teachers, lower elementary, and upper elementary.

Light Zebra Mussel Humor

History

Zebra mussels were discovered in the Great Lakes in 1988 and quickly began to spread like wildfire. For the past 200 years, these foot-slicing mussels have been invading the western and central European waterways. Native to western Russia, specifically the Caspian Sea, these mussels were able spread through canals and be transported by clinging onto ships. It is believed that the zebra mussels made way to the Great Lakes by catching a ride with a transoceanic ships to Lake St. Clair in 1985 or 1986. Since their appearance to the Great Lakes in the 1980’s, the zebra mussel and quagga mussel population is expected to be at about 10 trillion! That’s a lot of mussels!

Yearly Spread of Zebra Mussels from 1986 to 2011

Ramification

Economic

The zebra mussels colonize in clusters. The mussels replicate at an incredible rate. The problem with an invasive species that is able to colonize in clusters and at an expedited rate is the degree of clogs and clusters of the mussels. Mussels are able to attach to things like intake pipes, dock posts, boat propellers, etc. The effect zebra mussels have on municipalities’ public works results in a dramatic increase in maintenance of intake pipes from affected waterways. “The economic impact of these invasive mussels to hydropower, agricultural irrigation, municipal water supplies, and recreational boating has been estimated to be $43 million per year (Robinson et al. 2013).” Zebra mussels also have an adverse effect on the amount of money generated by the fishing industry. The fishing industry consists of licenses, fishing charters, and fishing related tourism. The last economical effect the zebra mussels have is tourism. One of the circumstance zebra mussels affect is the algae bloom. Think of going to the beach with the water being covered in algae, you can thank zebra mussels. Though they clean and clarify the water, the clearer the water, the higher blooms of algae and bacteria.

Ecologic

The mussel’s continual movement is filtering the plankton. Through filtering, the mussels change the dynamic of the food webs within the ecosystem. The consumers (fish) have a reduced selection of food that they are able to eat and the reduction of prey fish is caused by the reduction of plankton. In Lake Huron, the population of the Atlantic and Coho salmon have decimated. Water quality also affects the ecology of the water. The cleared water allows for increase in temperatures in the water which allows for the growth of bacteria and algae. This can impact the other living organisms in the body of water in ways they are not used to.

Zebra Mussels covering the walls of a dam

Remediation

The introduction of zebra mussels to the Great Lakes ecosystem has caused irreparable damages to the environment and businesses that call these lakes home. The extent of damage is dependent on several factors, but it is estimated that upwards of $40 million is lost due to the surge of zebra mussel population in our lakes. Efforts to lessen the spread of zebra mussels falls primarily on the individual. Things such as cleaning mud, plants, or animals from fishing/boating gear, removing water from all equipment, and cleaning anything that has come into contact with a body of water. The efforts to eradicate zebra mussels in Michigan is ineffective, with most efforts going towards prevention as opposed to eradication. Because of this the effects of these prevention efforts does not give a tangible estimate of its success.

Although eradication efforts seem bleak, there has been a promising new development in the introduction of Zequanox: dried, dead cells from a common North American soil bacterium known as pseudomonas fluorescens. The introduction of this bacteria works by breaking down the stomach lining of zebra mussels. The bacteria works quickly and effectively to lessen the population of zebra mussels without harming any native plants or animals through its introduction to the water source. It is hopeful that it will be introduced to large waterways within the near future.

Treating Zebra Mussels with Zequanox in a sectioned area of Christmas Lake, MN

What Now?

The truth of the matter is that regardless of our personal feelings toward the introduction of zebra mussels into the Great Lakes, they have drastically changed the ecosystems they inhabit. While overall fish and wildlife populations have decreased, aquatic plant life has increased. Such changes may seem problematic for those who make their living from the fishing industry, however, those in the diving world view the increased water clarity to be a welcoming change. The question now remains as to what the future holds for these little filter feeders and the Great Lakes that they have come to call home.

As you can see, the topic of zebra mussels provides a serious conundrum for all of us who live in the Great Lakes region! What a great topic to explore with your students! As we did with this topic of invasive species, we weighed both the positive and negative perception of zebra mussels and their impact. Such a topic can provide students with the opportunity to enhance their science skills. Exploring various sides of an argument and determining what constitutes a solid argument is a social skill that is necessary for the future in any field and sorting through scientific data and distinguishing reliable sources helps provide the backbone of the arguments. Another science practice that students need to accumulate is learning to design experiments and brainstorm creative solutions to a problem which opens the gateway for creativity with the sciences. In the end, having students construct their own views about an issues provides independence in their thought process and affirming their beliefs rather than blindly accepting any "truths" from anyone. The extensive links below assist in building the science practices for students.

Happy Exploring!