Invasive mussels have increased water clarity. That has led to a bloom in the sunlight-loving Cladophora that eventually dies and burns up massive amounts of oxygen as it decomposes on the lake bottom. That has opened the door to botulism-causing bacteria that thrive in oxygen-starved environments. The invasive mussels, many biologists believe, suck up those bacteria and are, in turn, eaten by gobies. The poisoned gobies become paralyzed and are easy prey for birds like loons, grebes and gulls. The birds die.
