What's ugly, smells, kills dogs? Blue-green algae

Waterways across the upper Midwest are increasingly plagued with ugly, smelly and potentially deadly blue-green algae, bloomed by drought and fertilizer runoffs from farm fields, that's killed dozens of dogs and sickened many people.

Aquatic biologists say it's a problem that falls somewhere between a human health concern and a nuisance, but will eventually lead to more human poisoning. State officials are telling people who live on algae-covered lakes to close their windows, stop taking walks along the picturesque shorelines and keep their dogs from drinking the rank water.

Peggy McAloon, 62, lives on Wisconsin's Tainter Lake and calls the algae blooms the "cockroach on the water."

"It is like living in the sewer for three weeks. You gag. You cannot go outside," she said. "We have pictures of squirrels that are dead underneath the scum and fish that are dead. ... It has gotten out of control because of the nutrient loads we as humans are adding to the waters."

Blue-green algae are common in waters but not every lake develops serious problems until plentiful "man-induced" nutrients like phosphorous arrive, said Jim Vennie, a Wisconsin Department of Natural Resources expert. The toxins released by the algae can be deadly. Symptoms include rash, hives, runny nose, irritated eyes and throat irritation.

No people have died in the U.S. from the algae's toxins, according to Wayne Carmichael, a retired aquatic biologist and toxicology professor in Oregon.

Many, however, have gotten sick: "Sooner or later, we are going to have more acute human poisoning," Carmichael said.

The scum has killed dozens of dogs over the years — including at least four in Oregon, three in Wisconsin and one in Minnesota this summer. Wisconsin wildlife experts are warning duck hunters with dogs to be extra cautious this fall. "If the water is pea-soup green, be sure to have clean water along to wash the dog off," Vennie said. "Don't let it drink the water."

Fewer than 100 lakes in Wisconsin typically have some problems with algae bloom each summer and the ones in western Wisconsin causing so much discomfort this year are being fueled by a perfect storm, Vennie said. The last month has seen little rain, warm, sunshiny days and little wind.

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