Acid rain is damaging plant and animal life in about 19,000 Ontario lakes, according to a study by the provincial Environment Ministry.
The report, which is the first to estimate with any accuracy the extent of acid rain damage to lakes in Ontario, found that there are more than 7,000 very acidic lakes in which most of the common fish have died, said Bernie Neary, supervisor of Lake Management Studies at Dorset.The other 12,000 lakes are acidic enough to damage other forms of plant and animal life, said the report, which is a statistical extrapolation of data collected between 1978 and 1989 from 6,000 of Ontario's more than 250,000 lakes.
Recent research is showing that biological damage is occurring in lakes that would not be considered acidified under the old definition, Neary said.
"The traditional yardstick was whether or not there are fish in a lake. We find that they are among the more tolerant organisms in a lake," Neary said. "The take-home message here . . . is that there are many parts to an aquatic food chain and there are varying levels of sensitivity."
Michael Perley of the Canadian Coalition on Acid Rain said he was not surprised by the high number of damaged lakes. The study confirms rough estimates made five years ago by the department of Fisheries and Oceans.
"I don't think it will surprise very many people when they hear that order of magnitude, unfortunately."
About 7,300 of the lakes are in the Sudbury region, where acidification has been caused primarily by emissions from local bridge smelters.
Another 11,000 are in areas affected by the long-range transport of sulphur pollution and delivered in the form of acid rain and snow.
The U.S. Congress will start again next week considering the clean-air bill sponsored by the Bush administration. The bill is designed to cut sulphur dioxide emissions by 10 million tons a year by the year 2000 or, at the latest, 2004.
The Canadian government is counting on that legislation to cut U.S. acid rain emissions that damage Canadian lakes.
Last week, however, several governors from Western states called a news conference to say they did not want to have to pay for what they perceived to be a problem caused by Eastern states.
(Distributed by Scripps Howard News Service.)