Which of the following best describes the impact of zebra mussels on the Great Lakes food web?

Zebra mussels are an invasive species in the Great Lakes that have a significant impact on the aquatic food web. The correct answer highlights the consequences of zebra mussels filtering water and their consumption of phytoplankton, which is a primary food source for many aquatic species, including young fish. By removing large quantities of phytoplankton from the water, zebra mussels decrease the food availability for these fish and other organisms that rely on phytoplankton for sustenance. This can lead to a cascading effect throughout the food web, impacting not only fish populations but also predators that depend on those fish for food.

In contrast, while some may argue that an increase in water clarity could benefit other aquatic plants, this doesn't offset the negative effects zebra mussels have on the overall food supply for many organisms in the ecosystem. The presence of zebra mussels can shift the balance of species interactions and reduce biodiversity as native species struggle to compete with this highly efficient filter feeder.