“Can my cat contribute to climate change?” » Yale Climate Connection

A reader asked:

To what extent are cats responsible for climate change?

To answer this question, we asked Sara Peach, editor-in-chief of Yale Climate Relations and a longtime environmental journalist. This is her answer:

Fans of the world's furriest and most lovable animals gather together with switchblades on their feet. Let’s answer this question by delving into the scientific literature.

On the plus side, domestic cats (Felis catus) don't produce climate-warming pollution from flying on private jets or burning gasoline on their way to work. They got into the habit of lounging around naked – it wasn’t wasteful fast fashion to them.

But they do have a bad ecological reputation for killing billions of birds. Like other cats such as lions, tigers and pumas, domestic cats belong to the order Carnivora, which means “carnivores” in Latin. These organisms rely on animal protein to survive.

Specifically, the cat's diet must include an amino acid called taurine, which is only found in animal proteins because the cat's body cannot make it. This is one reason why they rely on us, their human servants, to provide them with meat-rich pet food. Raising farmed animals like cattle and poultry to feed our pets contributes to climate change, most notoriously because cow burps produce methane, a gas that traps heat in the atmosphere.

In Mexico, raising enough meat to keep an adult house cat healthy for a year would produce 941 kilograms (2,075 pounds) of warming gases, according to one estimate that has not been peer-reviewed. A more detailed peer-reviewed study using a different methodology calculated that U.S. pet dog and cat food produces 390 kilograms (860 pounds) of climate pollution per animal per year. This is roughly equivalent to the amount of climate pollution emitted by a car traveling 1,570 kilometers (975 miles).

Many cat foods contain meat by-products that humans don't commonly eat, such as organ meats, blood, and bones. Using these scraps in pet food reduces waste and climate pollution. But as one study points out, the trend toward “humanizing” pets is leading some consumers to buy larger quantities and higher-quality meat-based pet foods.

So what can be done to reduce cats’ impact on the climate? A plant-based diet has a much lower climate footprint (paw print?) than a meat-based diet, so some researchers are exploring whether domestic cats can survive on a vegan diet that includes taurine supplements.

A 2023 study showed that cats on a vegan diet are healthier than their carnivorous counterparts. But the study has been criticized for methodological issues. Most notably, some so-called “vegetarian” cats are allowed to roam outside unsupervised, where they may eat birds or rodents.

There is still a lot that is unknown about a healthy vegan diet for pet cats.

Alexandra Whittaker, associate professor in the School of Animal and Veterinary Sciences at the University of Adelaide, was responding to research on vegan cats.

“Previous research has shown that cats on vegan diets suffer from severe muscle deficiency. Owners may be able to provide these nutrients through supplements, but this requires an understanding of cat nutrition, or some sound advice from an animal health professional. ” she added. “It might be wise to wait a while before cutting Felix off from eating meat altogether.”

Another option: Consider the advice of UCLA scientist Gregory Okin and adopt a smaller vegetarian or omnivorous pet instead of a cat. Many domestic birds, rodents and reptiles fit the bill. Rats are easy to kiss, right?