The Great Lakes area once supported an abundant number of freshwater mussels (Mollusca: Unionacea). The invasion of Zebra mussels (Dreissena polymorpha) has decimated these populations, by outcompeting native mussels in dispersal rates, and reproduction, due to enhanced survival mechanisms. Understanding the mechanisms that have allowed Zebra mussels to out complete native fresh water mussels, will provide insight into possible mechanisms that can stop the spread of Zebra mussels, and help with the survival of native mussels.
Griffiths et al. conducted length-frequency analysis of the Zebra mussel population, before 1988 (prediscovery) and between …show more content…
This research shift was an attempt to provide insight into the recovery of native mussel populations within the abundant and harmful Zebra mussels. Strayer and Malcom 2007 conducted a fourteen-year experiment in which they collected samples of unionids, between mid-June and August of each year, in water depths less than 3 meters. Zanatta et al. took a similar approach by sampling for a three-year period. Both experiments found that all species dramatically declined following the years of Zebra mussel infestation. The experimental data also correlates in that the species Elliptio occurred 9%, within Zanatta et al. sampling, between 1999 and 2000; within Strayer and Malcom 2007 data, Elliptio increased in population after 2000. Furthermore, both experiments discussed that shallow waters of Lake St. Clair supported Unionid refuge sites or populations, although the mechanisms to why this could be were not discussed in either paper. Additionally, both experiments did not account for zebra mussel dispersal rates, commercial activity, and movement of Unionids in and out, within the sample …show more content…
Furthermore, the articles also emphasized the ongoing population decline of native mussel species is no longer so. That native mussels are taking refuge and that their populations are steadily increasing. This is proof that the effects and populations of the Zebra mussel can be controlled; however, the mechanisms or conditions in which these native mussels are able to take refuge is unknown. Further experimentation, should be conducted to find what these mechanisms are, so that they can be replicated to further increase native mussel