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Conditions Right for Blue-Green Algae

The North Dakota Game and Fish Department advises outdoor enthusiasts to be cautious with their dogs around water this time of year, due to potential health hazards associated with blue-green algae.

Wildlife veterinarian Dr. Dan Grove said it only takes a few hot days for blue-green algae to bloom. “We have experienced many days like this already this summer, and with warmer temperatures yet to come, conditions are right for lakes, ponds and wetlands to become contaminated by toxins produced by blue-green algae,” he said.

Shallow, stagnant water, with moderate to high nutrient content, provides an optimum environment for blue-green algal growth. Water or wind movements often concentrate blue-green algae along the shoreline, and eventually the bloom appears as a blue-green “scum” floating on the surface. The threat diminishes, but is not completely eliminated, once the weather cools.

Dogs shouldn’t drink or swim in discolored water or where algal blooms are apparent. If dogs practice retrieving in these conditions, Grove said they should be rinsed off immediately and shouldn’t be allowed to lick their coat.

For additional information about the effects of blue-green algae blooms visit the North Dakota Department of Health website at ndhealth.gov, the North Dakota Department of Agriculture’s Animal Health Division at 701-328-2655, or a local veterinarian.