Environment committee  It depends on what part of the lake you're looking at, because we have a shallow western base—

Environment committee  Okay. The western basin is a case in point, which is perhaps the best study of the Great Lakes because it's been subject to pollution for the longest time. When conditions are good, the water mixes, there's enough oxygen there, and the mayflies come out as fish flies and do very well.

Environment committee  I'm not familiar with that.

Environment committee  Perfluoric?

Environment committee  I'm not that familiar with it.

Environment committee  I didn't refer to them specifically. The environmental estrogens can be byproducts of things like PCBs, but they also come in through personal care products. They've been documented to have influences at the site where sewage treatment plants may release their materials, but there's so much dilution by the water itself that those effects have not been seen at larger scales.

Environment committee  Thank you. Shoreline development, episodically low water levels, as Mr. Sweetnam has described, and most especially the threats of invasive species are the really major threats. The prospect of Asian carp entering the Great Lakes through the Chicago channel and elsewhere is perhaps the most serious threat of causing changes in the entire food web.

Environment committee  Thank you very much. I'm very pleased to be invited to speak. My name is Jan Ciborowski. I'm a professor in the department of biological sciences at the university. I've been there since 1984. I'm an aquatic ecologist interested in understanding the relationship between environmental stress and the biota that are affected by it.