How to Protect Your Dog from Blue-Green Algae This Summer

During the summer, many dog owners enjoy taking their dogs to lakes, beaches, and rivers to give them a chance to cool off and flex their swimming muscles. 

On these adventures, it’s important to keep an eye out for toxic cyanobacteria, sometimes called blue-green algae, that can quickly turn a fun adventure into a fatal accident. These bacteria are poisonous to dogs when touched or consumed, and they are especially common in the summer, when warm, sunny conditions promote accelerated growth. Some regions have issued warnings already this year.

The best way to keep your dogs safe this summer is to keep them away from any suspicious water. Here’s what else you need to know. 

What Are Cyanobacteria? 

Cyanobacteria are a type of photosynthetic bacteria that grow in water systems when they have access to nutrients such as phosphorus and nitrogen as well as sunlight and warm temperatures. When these bacteria grow in large quantities—known as a bloom—they can produce toxins that are dangerous to humans, dogs, and other animals. Technically, it's not algae.

“The exact toxins and the amounts that are produced is really a consequence of how much nutrient is in the water, what the growing conditions are, the temperature, the light, and so forth,” said Dr. David Caron, a microbiologist and professor at the University of Southern California. 

It is most common for cyanobacteria blooms to form in lakes, ponds, and other bodies of still, fresh water, but they can also be found in salt water. The blooms often emerge at the edge of the water where it is especially warm and still, two conditions in which cyanobacteria thrive. They can occur throughout the United States.

Blooms can look like foam, scum, or mats floating on the surface of water, though they sometimes stay below the surface. They are often bright green but can appear blue, brown, and red. Not all cyanobacteria blooms are toxic, but it is impossible to tell by looking at it, according to the Centers for Disease Control and Prevention.