MINNEAPOLIS (WCCO) — The Minnesota Pollution Control Agency is advising pet owners to be cautious around lakes and slow-moving streams after the death of a dog in Sherburne County last weekend.

The MPCA says Brock Tatge and his family, who live on Prairie Lake, were enjoying their Sunday when their dog, Copper, became ill after fetching a tennis ball from the lake.

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“We noticed that Copper went on shore, began vomiting and panting very hard, and just looked very sick,” Tatge said. “I carried him to my truck and brought him to the vet’s office.”

Copper died later at the veterinarian’s office. His illness hasn’t been confirmed but the veterinarian who examined him believes that he became ill after ingesting toxins from blue-green algae.

Now, the MPCA says pet owners should check water conditions before letting their pets go into the water. Blue-green algae can look like green paint, pea soup or floating mats of scum.

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If animals do enter the water with heavy algae growth, they should be hosed off right away before they have a chance to lick themselves clean.

It looks like more algae is on the way, too.

“This year’s unusually heavy rainfall has carried tremendous amounts of nutrients into Minnesota lakes,” said MPCA scientist Steve Heiskary. “If the rain slows down and we move into a period of hot, dry summer weather, we could see an exceptional number of algal blooms across the state in the coming weeks, even in lakes that do not normally experience them.”

People should never swim in water with blue-green algae, and exposure to the toxic algae can include skin irritation, nausea and eye, nose and throat irritation.

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For more information on the algae, click here.