It is a beautiful day in la Mauricie National park, in Quebec, a perfect day to paddle on lake Wapizagonke, one of the many lakes of the park. A common loon dives under your canoe and emerges with a trout hanging from its bill. The same day, you also watch a moose cow and calf, a few Canada geese and a golden eye.
It seems all this wildlife calls La Mauricie National Park a paradise and you are happy, and yet...
Most of the park's visitor aren't aware that the lakes are poisoned by mercury. The mercury is released as a gas from coal-burning power plants in North America and as far away as eastern Europe and China and carried here by air currents. It falls into the lakes, attached to dust particles, rain and snow.
And that’s where it becomes perhaps the key threat to the reproduction and survival of Canada’s common loons. As predators, loons are at the top of the food chain, feeding heavily on mercury - contaminated fish, accumulating mercury in their tissues with every bite, in turn making them less able to fight infections and more likely to have endocrinal problems.
During a long term study in the park, one male was captured on lake Caribou. He had a feather mercury concentration more than twice as high as any other loon in the study. It was the highest known level of any loon tested in North America.

During summer 2006, I was on assignment to investigate the facts about threats on the common loon. There is not only mercury, but lead, acid rains, flooding and other natural causes, harassment by humans etc.. I also witnessed the work such as that being done in La Mauricie National Park and elsewhere in North America to preserve loon populations.
My story was published in the January / February 2007, issue of Canadian Wildlife and Biosphere, both magazines of the Canadian Wildlife Federation (available for members only).
For those who aren't members of the Federation, it is possible to read the story by clicking here.... The Call Of the Wild