Project
Quantifying biological productivity and diversity at a Lake Superior lakemount
Recent work has pointed to lakemounts as potentially critical features in large lake ecosystems, which, like seamounts in ocean environments, appear to be \'hot spots\' that play a disproportionately large role in supporting ecosystem biodiversity and production. As such, lakemounts may represent refugia for coastal populations of fish suffering from human disturbance. Several mechanistic processes have been reviewed and proposed to be important at lakemounts in driving greater regional production. These processes include upwelling of deep, nutrient-rich hypolimnetic waters against the abupt topographies of lakemounts, both from large-scale currents and internal seiche events during stratification. Lakemounts also provide substrate for benthic organisms in an otherwise pelagic environment. Advective forces due to large-scale currents can also lead to deposition of algae and zooplankton through leeward eddy retention, and the trapping of vertically migrating organisms, making them vulnerable to predation by resident consumers. Here, we evaluated the ecosystem productivity of lakemounts through a comparative approach, collecting size and abundance data of organisms at the Superior Shoal lakemount by use of a Slocum glider. These data are currently under analysis for comparison with other ship-based and up-looking acoustic data to better understand both spatial and temporal variation in organism distributions surrounding Superior Shoal.
Project Datasets
Lake Superior Shoals 2025 survey
Dataset will ultimately be several linked datasets including both uplooking stationary and downlooking (ship-based) active hydroacoustic surveys; stable isotope data for various food web components (phytoplankton to fish); phytoplankton and zooplankton density and size data; ADCP data; spatially-explicit glider-based CTD and acoustic data; ROV survey data around shoal structures.