It was hot last August and the waters of Lake Superior near Grand Marais, Minnesota, looked inviting. First, Lynne Buchanan’s son’s girlfriend and then Buchanan’s 55-pound labradoodle, Takoda, jumped in. Finally, Buchanan herself joined them. The water looked clear but she noticed debris floating toward the surface from the rocks on the bottom, stirred up by their splashing and paddling.
After the swim, Buchanan left Takoda with her son and went for a hike. A few hours later, she got a text: “Your dog is in total distress. Get home.” Takoda had run off into the woods and started vomiting. By the time Buchanan arrived, there was nothing more coming up. Takoda was foaming at the mouth and making desperate sounds. “I thought he was dying,” Buchanan says.
Water from the pond was tested four days afterward and showed relatively low levels of a toxin, not enough to confirm that toxic algae caused the dogs’ deaths or to rule it out. (Cyanobacteria blooms can appear and disappear quickly.) Martin got the city to put up a sign at the pond warning of the danger. She continues to push for signs at other ponds and is working with vets to inform their clients about the risk.
Experts say the best way to protect dogs is to keep them away from outdoor bodies of water—ponds, lakes, sluggish rivers, even bird baths—especially in the summer. That means leashing dogs, says Hodges. “If you had a toddler, would you let your child run ahead of you on the trail [out of sight]?” she says. “Think of your dog that way.”
What to watch for
Signs of cyanobacteria poisoning include vomiting, diarrhea, excessive drooling, stumbling, stiffness, tremors, weakness, difficulty breathing and convulsions.
If your pet has swallowed blue-green algae—and especially if she develops these kinds of problems after exposure to water, mud or debris along the shore—rinse her coat off as soon as possible, call a vet to alert them to the emergency and rush your dog for medical treatment. If you can, collect a water sample. If tests confirm toxic cyanobacteria, officials can place a warning sign.
The fastest-acting toxins attack the nervous system and can kill dogs within 24 hours. Slower-acting toxins attack the liver and can kill within several days.