Zebra mussels are actually quite destructive to the ecosystem, and quickly lead to waters that are choked with vegetation (because light can penetrate deeper in

Zebra mussels are actually quite destructive to the ecosystem, and quickly lead to waters that are choked with vegetation (because light can penetrate deeper into the water), and lacking the sorts of food consumed by filter feeders that form the base of the food chain. There are some species of fish that prefer the thicker vegetation, but fish populations overall decline significantly when zebra mussels invade.