What has happened to the zebra mussels?
Currently the students are involved in a joint research project that involves the data that we have collected from our monitoring sites on the Thunder Bay River. Recent data trends show that zebra mussel population has drastically declined in the last few years in Lake Huron and data we have collected this fall has shown a drop in the size and overall population of the zebra mussel at one of our testing sites. My students have asked the question, “Why is this happening?” Our hypothesis is focused on two things; that the zebra mussels have over populated themselves that they ran out of food or that another invasive species is out competing the zebra mussels.
We want to expand our project and increase our research capabilities. My students have diligently worked on gathering background information, testing and monitoring our sites and used the data from those test sites to create their own research question. We have collected samples from five sites this fall, which includes three river sites and two sites from shipwrecks. Divers from the Thunder Bay National Marine Sanctuary collected two samples from a deep water wreck and shallow water wreck. We hypothesized that the shallow wreck had dead zebra mussels attached and the deep wreck had health and thriving quaggas. On November 5th we processed those samples and our predictions were not completely correct. The deep wreck had only quagga mussels on it and they were all alive in the sample we took, but the shallow wreck had living zebra mussels on it, but had nearly twice as many quagga on it. Based on these recent finding, the students are working to redefine our hypothesis and develop a research process that will lead us to a more conclusive answer to our research question. We will repeat these same tests and collections in the spring, but the students want to use the underwater remote operated vehicles to collect our own samples. In previous years we have used the ROVs for simple data collection, but this will challenge the students to come up with a way to bring live mussel samples from the bottom of the lake to the surface.