July 23, 2009
What’s Really Down There?
Today’s topic was “Life in Lake Erie”. With our lectures, lab work and activities we got a great idea of what really is down below the surface of the lake. Not only did we find out who lives there but also how each of the species interact with each other and their environment—lake ecology.
Dr. Dave Jude, a biologist and ichthyologist from the University of Michigan gave a lecture to us providing us information on what the lake looked like in the past, what it looks like today and what the future may hold for Lake Erie. Characteristics of our lakes in the past were well oxygenated water, high biodiversity and well forested coast lines. As we compare that to what the lakes are today, things have changed. Much of the lake has seen destruction of habitat, invasion of exotic species, introduction of toxic substances, and over fishing. With the use of science and education we have designed ways to improve our lakes by finding ways to regulate fish species, controlling contaminants entering the system, and altering fishing regulations. We seemed to have learned from our mistakes in the past, but find that there are always new problems that throw the balance of the ecosystem out of balance. It is a constant challenge.
To get a better handle on what the present state of the lake is we took some actual samples from the lake to bring back to the lab for testing. The rainy day did not hold us back and we were able to collect phytoplankton and zooplankton using plankton nets. We also collected bottom sediment using a Ekman dredge and we even trawled for fish using a bottom trawl. With our boat full of specimens we headed back to the lab to really see who lives in Lake Erie.
Back at the lab all the teachers were excited to examine our catch. We set up stations in the room where we could view and identify phytoplankton, zooplankton, benthic invertebrates and different species of fish. We combined all our identification data to come up with how each of the species fit into the many food chains in the lake.
Dr. John Gannon, Senior Scientist from the International Joint Commission, and ecologist, helped us interpret our data. He provided us a better understanding of the changing food web in the lake as invasive species are introduced, and our coastal waters that enter the lake change. The upper Great Lakes have a simple system compared to the highly diverse and productive system of Lake Erie. He stressed that we need a better understanding of ecology of our coastlines and put effort into habitat restoration of wetlands, streams and coastlines. To accomplish this educating the public will be vital as well as multidisciplinary science. This is where scientists from two different fields team together to improve and restore our Great Lakes.
This evening was spent in our work groups processing all the information that we took in these past 6 days. How are we going to take all this amazing information and put it to use in our classrooms? As teachers we look forward to organizing these experiences and knowledge in a fashion that we can excite our students to science and increase their appreciation of these Great Lakes. We all, young and old, need to be caretakers of the lake and voices for the future of the lakes.
Did you know?
- There are degree programs that combine both biology and engineering. Many different universities now have biosystems engineering programs where students learn how to use both biology and engineering to solve problems in biological systems.
- Botulism E contamination occurs from rotting algae, which is then filtered by zebra mussels, which in turn is eaten by round gobies, which are then eaten by Loons. A loon only needs to eat 2 gobies to die from botulism E poisoning.
- Fish have a stone-like structure called an otolith in their head that helps them to maintain their balance much like our inner ear. Scientists can use the rings on the otolith to determine the age of the fish to the exact day.