Invasive Mussles Project

Invasive Mussel Project – Mitigation Recommendations Needed

Both the zebra and quagga mussels have been shown to be extremely destructive in the Great Lakes (NOAA, 2008). Originally from Eastern Europe they were introduced here in Canada through ballast water discharge from ships, first the zebra mussels in the 80’s and then the quaggas in the 90’s. As of late it appears the quagga mussels can outcompete the zebra mussels due to their ability to tolerate colder temperatures, live I soft sediment and have a much longer siphon for feeding. The NOAA’s Great Lakes Environmental Research Laboratory (GLERL) have been monitoring the issue since the arrival of the quaggas. The map below (Fig. 1) illustrate how quickly the quaggas have dominated the area.

Figure 9. Density of Quagga Mussels in Lake Michigan determined in the year 2000, 2005 and 2010 (NOAA, 2008)

Food production for native species have been declining since the introduction of these invasive mussels and in particular the shrimp-like organisms called Diporeia as shown in the Figure 1.

Figure 10. Density of Diporeia in Lake Michigan in 1994/1995, 2000, 2005 and 2010 (NOAA, 2008)

Along with increased mussels and decreased Diporeia researchers have seen an increase in the size and number of harmful bottom-dwelling alga in the Great Lakes. One such algal is called Cladophora, which makes its way on to beaches in clumps rendering the beaches unpleasant due to their unsightly and smelly nature and also impact nutrient levels in the water (NOAA, 2008).

Figure 11. Phytoplankton production from 1983 to 2008 in the springtime in southern Lake Michigan (NOAA, 2008).)

The decline in Diporiea has resulted in some fish changing diet to a less nutrient rich diet in order to survive. As recreational fishing has a huge presence in the Great Lakes the presence of these invasive mussels has taken its toll on the economy (NOAA, 2008). Alongside this, the tourism industry has been impacted due to the less enticing beach quality that has resulted from the Cladophoral blooms (NOAA, 2008). Consequently, the GLERL has hired you to further investigate why and how this relationship is taking place in order to determine what mitigation strategies may be implemented.

Your Role

You have been hired by the Great Lakes Environmental Research Laboratory (GLERL) to investigate the relationship seen between invasive mussels and the harmful algal blooms. The GLERL is interested to know how these two populations are connected and what mitigation strategies can be implemented to help. Due to budget constraints you and your partner will need to conduct this research in lab and provide the GLERL with a proposal for approval prior to initiating your research. (The GLERL is your TA in case you were wondering). Before you can begin developing your proposal you must first become immersed in your topic. You and your partner will need to source out 5 primary source papers related to this topic.