They still number in the billions, but zebra mussel populations around New York are declining, state environmental officials say. Not enough to eat. And, according to information obtained from recent dives in the lake, the mussels also are up to 11 millimeters smaller. Our system will never go back to what it was,'' said Edward L. Mills, director of a Cornell University field station on Oneida Lake. ''Native species are being lost and contaminants are concentrated. We have 20 percent of the world's fresh water in this area.
Scientists say that the scarcity of food is causing quagga mussels to replace zebra mussels.
In Oneida Lake, bass populations are increasing because the clearer water encourages aquatic plant growth, Mills said. However, clearer water doesn't mean cleaner water. Airborne and groundwater toxins, including PCB and mercury, are becoming concentrated at the bottoms of lakes in the remaining algae plants. It's possible that an increase in contamination in algae plants eventually will lead to an increase in contamination in the fish that feed on those plants. Clearer water also may contribute to increased mortality in fish larvae because they are more vulnerable to being found and eaten by other fish.