Lake Mendota Boat trip - June 27 2018

On a cloudy yet beautiful June 27th morning, John Magnuson and his partner, David Harring, took 12 attendees across Lake Mendota – in two boats – to view the full expanse of the Lakeshore Nature Preserve and learn about the region’s history. We were told stories of previous inhabitants of the preserve–Black Hawk and Winnebago Native American tribes, the Frautschi family, farmers–and the transformation of  the landscape over the years. Our guides also informed us about the important role of the limnology building, which due to its position between the Preserve and the urbanized city, has on occasions protected construction (e.g. of roads and parking lots) from occurring within the Preserve. Attendees were also given the opportunity to use some limnology gadgets to learn more about Lake Mendota. We raked the floor of the lake to find and identify native and invasive plant species, sampled water from the various depths of the lake, and collected and viewed microscopic zooplankton and daphnia. Summary and photos by Olympia Mathiaparanam, Friends host. 

John Magnuson added the following explanations to the photos of cyanobacteria and zebra mussles below: "The green microscopic organisms are a mix of several species of Cyanobactera (often referred to as bluegreen algae). These photosynthetic organisms contain gas vacuoles that cause them to float upwards in the bottle and in the lake to bring them to the upper sunlit layers required for photosynthesis. In the clear area at the bottom of the jar the small zooplankton have swum downward. In the lake they would hide from their predators in the deeper dark layers of the lake. The water below about 2 meters on this day was darker and would reduce their visibility to the young, small fishes that feed on small zooplankton. The two visible types of zooplankton were crustaceans called Copepods and Cladocerans.
 
The mussel on the small dead branch that we raked from the bottom in shallow water is the Zebra Mussel (Dreissena polymorpha). A graduate student at the Center for Limnology has been researching this species since it was first discovered by a limnology laboratory class (Zoology 316) near the Limnology pier in 2015. See this Madison News article on Zebra Mussel quickly filling Lake Mendota or google: Center for Limnology Zebra Mussel." ​