By Jill Langlois
February 3, 2025
Photo by FatCamera/Getty Images
Heat waves, floods, wildfires, worsening air quality, and outbreaks of communicable diseases are all exacerbated by climate change, and they’re affecting not only the well-being of our planet but also the health of those who live on it. And humans are not the only ones experiencing everything from worsening seasonal allergies to increased respiratory and cardiovascular disease to severe injuries caused by extreme weather events or natural disasters. The pets we share our homes with feel these effects too. Here are ways to keep them healthy and safe, once you understand the risks.
Unseasonable, fluctuating temperatures—whether they rise and result in higher heat or fall and leave conditions colder—cause some of the most common climate-related health issues, running the gamut from heat stroke to hypothermia.
“All animals have a thermal comfort zone,” said Colleen Duncan, a professor at Colorado State University’s College of Veterinary Medicine and Biomedical Sciences and coauthor of the book Climate Change and Animal Health. “And when you exceed that—too warm or too cold—they can suffer ill effects.
Rising temperatures can also lead to warmer water and the more rapid growth of cyanobacteria, also known as blue-green algae, which is toxic to dogs and can lead to seizures, respiratory failure, and liver failure.
“They go to swim in the body of water they always splash around in and, lo and behold,” said Duncan, “there was undetectable blue-green algae, and you get a very sick animal.”
Extreme weather events and natural disasters brought on or exacerbated by climate change can lead pets to get injured or to be displaced from their homes and separated from their families during emergency evacuations. And they can cause other negative impacts on pet health too. The smoke from wildfires can produce poor air quality, eventually leading to respiratory issues in pets. Floods can contaminate water sources and lead to an easier and wider spread of vector-borne diseases that insects carry—for pets, the main concerns are Lyme disease carried by ticks, heartworm disease from mosquitoes, and tapeworm from fleas. All of the insect carriers also thrive in hot and humid climates, so temperature increases along with flooding pose a particular risk.
Warmer, damper surroundings have also caused some experts to raise the alarm about mycotoxins. These fungi grow on crops commonly used as cereals in pet food—such as corn, wheat, and barley—contaminating the chow.
Like humans, pets with pre-existing conditions and comorbidities—diabetes or cardiac disease, for example—are more at risk than others and are more likely to be impacted first. If your furry best friend happens to be a brachycephalic breed—short-nosed and flat-faced, like Persian cats, pugs, and French bulldogs—that also means they aren’t very heat tolerant, and respiratory issues can be a particular problem for them.
Age can also be an important factor in how your pet handles climate change, so pay close attention to any senior or very young animals you have at home.
And no matter what type of pet you have, if climate change has taken a toll on your socioeconomic well-being, their health could also take a hit.
“If people are struggling because their livelihoods have been impacted, they no longer have financial security, or they’ve been displaced by a disaster and they’re homeless, it makes it really difficult for them to care for their animals appropriately and sometimes to even keep their pets,” said Elise Anderson, regional lead for the rural and regional program at the nonprofit Vets for Climate Action.
Since pets can’t communicate when they’re feeling unwell, you’ll need to watch for signs: lack of energy, loss of appetite, vomiting, and diarrhea among them.
“None of the effects of climate change are really unique in the way that they might manifest,” said Duncan. “It’s impossible to look at an animal and say, ‘That is climate-associated illness.’… We already know what heat exhaustion looks like and what respiratory disease looks like. The problem is that they’re happening more often.”
The best thing you can do to protect your pet is have a prevention plan.
“It’s important to understand what the hazards are in your area,” said Duncan.
Asking your vet which conditions or diseases are common where you live and might be exacerbated by climate change, or if there are any illnesses that are new or changing in your area, is key. That information will help you keep up-to-date on which vaccinations your pet needs and how often they should get them, as well as any other preventative measures that should be taken to ward off diseases transmitted by parasites, such as ticks.
“In some areas, people might not have had to use tick prevention before,” said Anderson. “But it might be something that they want to consider doing as conditions in their region change.”
Paying close attention to information that influences public health, such as air quality alerts and heat warnings, is also important to keep in mind if you’re planning to take your dog on a walk or want to keep a close eye on the well-being of a high-risk pet.
Including your pets in your emergency disaster plan and having a well-stocked go-bag ready for the next wildfire, flood, or hurricane that affects your area can also help keep your pets safe and put your mind at ease.
“Find somewhere to go where you can take your pets with you,” said Anderson. “Make sure you have appropriate carriers or ways to transport your animals in your car, and if you have pets that need ongoing medication, make sure you have their prescriptions or medications ready to go, because you might not be able to get to your vet for days or even weeks.”
If you’re thinking about even more long-term solutions, Duncan suggests keeping sustainability in mind when shopping for your pet. Some pet waste collection bags are compostable, and collars and toys can be made of natural fibers, such as hemp and wool, rather than plastic and polyester. Being more mindful about the carbon footprint related to what and how much you feed your pet is also a good place to make changes by sourcing sustainable ingredients and being mindful of overconsumption. Animal obesity rates are on the rise because we are often feeding them too much.
“If we are feeding our pets 30 percent more than they should be eating, we are effectively just fueling this fire, which is in turn making our pets sick. I know it can be hard to cut back, but think about rewarding with play, with going outside, with time with owners, instead of always rewarding with food. It can help their health in the short term and give them a better place to live in the long run.”
Jill Langlois is a contributing writer for Sierra, and an independent journalist based in São Paulo, Brazil. She has been freelancing from the largest city in the western hemisphere since 2010, writing and reporting for publications like National Geographic, The New York Times, TIME and The Guardian. Her work focuses on human rights, the environment and the impact of socioeconomic issues on people’s lives.
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