The relative impacts of nutrient loads and invasive species on a Great Lakes food web: An Ecopath with Ecosim analysis | Semantic Scholar (2024)

A model of the ecosystem was fit to available data and the effects resulted in declines in large piscivorous rainbow trout and lake trout, followed by non-anadromous kokanee salmon, with little effect observed on an adromous sockeye salmon.

Simulation results showed that recovery of alewives is unlikely regardless of Chinook salmon biomass in Lake Huron, which implies that the shrinking prey base cannot support the same level of salmonine predators as that prevailed during the 1980s.

...

...

A meta-analysis of published studies and long-term monitoring data sets evaluated the effects of dreissenid mussels on the biogeochemistry, flora, and fauna of lakes and rivers across North America and Eurasia to find the largest effects were found in rivers, followed by littoral and pelagic habitats in lakes.

The results showed that dreissenid invasions were often, but not always, associated with subsequent TP and Chl declines, suggesting that a relaxation of TP standards would be unwarranted.

The nearshore shunt would require even more stringent P management for lakes strongly impacted by dreissenids to maintain nearshore water quality, and highlights areas in need of more research.

An equilibrium mass balance model (Ecopath) with a dynamic food web model (Ecosim) was combined to evaluate the ecological consequences of future alternative management strategies and the interaction of two different sets of life history characteristics for fishes at the top of the food web.

Impacts of these benthic invaders vary with site: in some shallow areas, habitat changes and the Dreissena → round goby → piscivore food chain have improved conditions for certain native game fishes and waterfowl; in offshore waters, DreissENA is competing for settling algae with the native amphipod Diporeia spp.

Growth of alewives Alosa pseudoharengus and lake whitefish Coregonus clupeaformis has declined since the arrival and spread of dreissenid mussels in Lakes Michigan and Huron to provide insight into the invasion's effects on fish growth and food web dynamics.

...

...