Environment committee  It's really critical that we look at habitat, because without the habitat we don't have the small fish and we don't have the big fish. This is actually one of the major things that our research is showing now. When you don't look after the breeding habitat, when you're only looking at the big fish, like the muskies that grow to 54 inches, what we're finding now in Severn Sound is that there are no more young muskies because the habitat is gone, because it has dried up, and there's no oxygen where there should be.

Environment committee  Changing water levels have implications for the volume of the water, obviously. So whether it's in the nearshore or on the offshore are actually two different things. I'm talking about the nearshore. For the nearshore environment a drawdown of half a metre or a metre, when your wetland on average is only about three or four metres, means that's a quarter of the volume of water.

Environment committee  To give you an example, it cost $4 million to build the structure to exclude carp from the marsh. That was in 1990 dollars. It costs annually still for us to take carp out of there and put good fish back in and that kind of activity. If you asked the people now if they had known in 1990 that this might happen to the marsh, when it was actually in really good health, and if they would have kept on pumping raw sewage into it, they would say no.

Environment committee  All right. I'm going to talk about the water levels. The water levels in Lake Michigan have fluctuated in approximately 30-year cycles over the past century. They range between 175 and 177 metres, but with a long-term mean of about 176 metres, above sea level. One of the many consequences of global climate change is there are lower than normal water levels in the Great Lakes, and we are seeing this now.

Environment committee  I want to first thank the committee for inviting me to come and share my concerns about environmental threats to the integrity of the Great Lakes. I am a professor of biology at McMaster University and I also serve as the director of the life sciences program. It just occurred to me that we're going down in age here.