From reading the literature as well as the reports that came out from the Great Lakes Fishery Commission, my opinion is there could be several reasons. One of them, which I think everybody is aware of, is nobody likes pesticides being put into drinking water supplies. Now, admittedly this pesticide biodegrades, but nevertheless it has a negative connotation. There is at least some evidence that this pesticide, despite the claim that it acts only against sea lamprey, in fact causes chronic effects in the very early life stages of lake sturgeon, for example. We know lake sturgeon is at the present stage endangered, or very close to being so.
The last and probably most important reason is that the cost of lampricide is literally going up almost every year. My understanding is that at the present time the cost of the chemical is in the order of $1 million per lake. It varies, I think, from about $800,000 to over a million, depending on the lake.
That's the overall control, but most of the control in fact relies on pesticides. I think the Fishery Commission can see the writing on the wall, in the sense that costs keep going up and up and the public doesn't like the fact that pesticides are being used in water in industrial quantities. It would probably be a very sensible idea to try to decrease the amount of it and come up with other methods that at least could complement the use of the pesticide.