The Great Lakes - St.Lawrence Research Inventory

The U.S. Army Corps of Engineers, Buffalo District (Buffalo District), through participation in the Western Lake Erie Basin Partnership and responsibility for the WRDA 516(e), 204 and 312 (a) programs, has been planning and working within the Maumee Basin to reduce the loading of solids and nutrients to the Maumee River and the western basin of Lake Erie.

LimnoTech is developing and applying a watershed model to the Blanchard River Watershed, a sub-watershed in the Maumee River Basin, Ohio. The primary goals of the project are to simulate erosion, sediment delivery pathways, and sediment delivery loads in the watershed; simulate fate and transport of nutrients; project benefits of conservation treatment strategies and best management practices; and support efforts to reduce erosion and sediment and associated nutrient delivery to Toledo Harbor and Maumee Bay.

Lake whitefish support the most economically important commercial fishery on Lake Michigan. Genetic analyses have indicated that the lake whitefish population in Lake Michigan is comprised of at least six genetically distinct stocks, resulting in a mixed-stock commercial fishery. Growth, age structure, condition, fecundity, and age at maturation could vary among these genetic stocks. Consequently, responses to exploitation could vary among stocks, supporting the need for stock-specific management.

LimnoTech is developing a linked hydrodynamic–sediment transport–advanced eutrophication model to inform restoration and management decisions in the Maumee River Watershed by creating a linkage between watershed activities and ecological endpoints of concern in the lower Maumee River and western basin of Lake Erie. Application of the modeling framework will include evaluation of how localized sediment accretion/erosion behavior changes relative to alternatives for dredged material placement, island building, etc.

To identify and understand the alterations in the Saginaw Bay ecological structure and function in response to stressors such as Dreissenid mussel invasion, nutrient loads, sediment loads, hydrology and water levels, and climate conditions, LimnoTech developed a coupled aquatic ecosystem modeling framework by linking EFDC (a hydrodynamic and sediment transport model) with an advanced aquatic ecosystem model (A2EM) that we developed by adding Dreissenid (zebra and quagga mussels) and Cladophora sub-models to our existing advanced eutrophication model.

Millions of lake trout (Salvelinus namaycush) have been stocked in the Great Lakes, yet self-sustaining populations are only present in Lake Superior and in remote areas of Georgian Bay. Successful reproduction of stocked lake trout has been hypothesized to be hampered in part by an inability to locate and spawn on highly productive reefs. Due to their nocturnal spawning habits, it is suspected that lake trout integrate nonvisual cues such as acoustical, electrical, tactile, or chemosensory for location of mates and coordination of reproductive behavior.

This project will investigate the genetic basis of feeding type in silver (Ichthyomyzon unicuspis) and northern brook (I. fossor) lampreys, two of the four lamprey species that are native to the Great Lakes. Silver lamprey adults are parasitic on teleost fishes, whereas northern brook lamprey are nonparasitic (i.e., do not feed at all following metamorphosis).

Several fish species rely on damage-released chemical alarm cues to assess local predation threats. These alarm chemicals are generally found within the skin and are released through mechanical damage effected by a predator. When detected by conspecifics and some heterospecifics, these cues can elicit both dramatic, short-term increases in species specific antipredator behaviours (e.g. fright response, freezing, decreased feeding etc) as well as long-term responses such as morphological or life-history changes.