For millions of Americans, there is nothing more enjoyable than going outdoors during the dog days of summer with our canine compatriots. From swimming in cool lakes to hiking America’s backcountry, there is no better companion or copilot for experiencing the joys of nature.

Unfortunately, some of those joys are being transformed into hazards. Our warming climate and years of inaction on clean-water protections, however, are making America’s waterways dangerous for dogs and other pets. Toxic algal outbreaks, which are transforming thousands of clean lakes, ponds, reservoirs and watering holes into slimy, green soups. 

These algal blooms are more than just smelly eyesores — they’re dangerous for pets, especially dogs. 

Tragically, the number of reported deaths in dogs from cyanobacteria (blue-green algae) has been on the rise. Dogs — especially those who love to play in water — can unwittingly jump into a pond containing a toxic algae bloom and become infected. The main routes of infection are ingestion: drinking contaminated water, consuming dead animals from the pond, or from grooming (licking) their fur that is soaked in toxic algae. Toxic cyanobacteria are particularly cruel and lethal in the way that they kill. Liver failure (hepatotoxicosis), neurologic toxicity (peracute neurotoxicosis) and gastrointestinal disturbances are the main systems through which they make pets, wildlife and people sick. The most ostensible symptoms of toxicity include vomiting, seizures, breathing problems and, ultimately, death. 

These bacteria can kill animals within 15 minutes of exposure.

But what makes these bacteria particularly pernicious is that there is no easy test to diagnose cyanobacteria toxicity and there is no known antidote. If a dog has been exposed to this bacteria, emergency veterinary care is always recommended, possibly including a medicated bath to help decrease further exposure.

Toxic cyanobacteria don’t discriminate when it comes to their lethality, so it is always recommended to wear gloves and use a face mask when rinsing your pet of suspected toxic algae residue to prevent human exposure. For those animals who have eaten fish or consumed the water from a contaminated pond and do not seek immediate veterinary care, there’s a strong possibility that the toxicity is going to be fatal. So when in doubt, veterinarians advise pet parents to avoid stagnant, unfiltered bodies of water in the summer. Unless the water is tested, it is impossible to know if the algae is toxic solely by visual inspection. Moreover, there may be multiple species of algae (a mix of toxic and nontoxic) in a given body of water, so even the most inviting waters can have hidden insidious dangers. Knowing that this bacteria can equally infect people, pets or wildlife makes avoidance the key to keeping pets and their humans safe. 

Local health officials and pet parents, however, can only do so much to address this perennial algal crisis. We need our leaders in Washington to act.

Harmful toxic algal outbreaks contaminate our clean water and expose pets, children and families to dangerous health risks, while also limiting access to recreational activities during the summer when more people want to be swimming, fishing and exploring the great outdoors.

The toxic algae outbreaks will only intensify as climate change disrupts water flows and warms water temperature and runoff pushes more pollution into our waterways. When conditions are right — which is increasingly happening due to climate-change-fueled heat waves and historic rainfall in parts of the country — algal outbreaks can threaten fresh water for entire cities.

An algal outbreak in Lake Erie has grown to the size of 20 square miles — echoing the 2014 algal bloom that forced almost half a million people to rely on bottled water after green slime instigated a three-day do-not-drink advisory. 

These incidents may seem like a new fact of life in our warming climate, but they don’t have to be. These ecological, public-health and drinking-water disasters are entirely preventable. 

The human-animal bond is beautiful in its complexity and its depth. Climate change is inextricably linked to the health of our pets. This issue not only affects humans but it affects every member of their families, including those who happen to be a different species.

Warnings and education are essential to protecting people and families but that is only a start. We need Congress to protect clean water to avoid these kinds of tragedies and help keep families together. 

By being good stewards of the planet, we take care of our pets, and ultimately end up taking care of our families.

Dr. Courtney Campbell is a California-based Board Certified Veterinary Surgeon. In addition to his surgical specialty, he also has a particular interest in infectious disease.