Surveys of lake trout spawning habitat at offshore reefs
In another collaborative project with the Illinois Department of Natural Resources, surveys are being conducted on preferred spawning habitats of lake trout (Salvelinus namaycush). A GPS and echo sounder are used to determine the depth and shape of the reef. A hydroacoustic towfish gives side-scan images which illustrates the types of substrate on that reef. This study can lead to a better understanding and conservation not only of lake trout, but eventually other essential fish living in Lake Michigan.
Waukegan Harbor Area of Concern
The International Joint Commission labeled Waukegan Harbor as an Area of Concern (AOC) after pinpointing six Beneficial Use Impairments (BUI) in 1987. This classification and six BUIs were a direct result of heavy manufacturing, chemical contamination, and PCBs found in the system. These contaminants had a direct negative effect on phytoplankton and zooplankton communities leading to high mortalities and the Degradation of Phytoplankton and Zooplankton Populations BUI to be designated for the Waukegan Harbor AOC.
By 2013, PCB concentrations in Waukegan Harbor were below the target level (0.2 ppm) prompting plankton surveys and water toxicity tests to be completed in 2017 by the Lake Michigan Biological Station. This study compared North Point Marina, a non-AOC location, to Waukegan Harbor, an AOC location. The results of this study found that there were no significant differences in the plankton community density or species richness between these two sites, however, strong seasonal shifts differed between the sites and the community structures were not similar. Water toxicity tests showed that AOCs had a lower water toxicity in comparison to non-AOC locations. The results of this study prompted a removal of the AOC and the Degradation of Phytoplankton and Zooplankton Populations BUI in Waukegan Harbor.
You can read the full report here.
