The climate cost of pets, particularly dogs and cats, is largely tied to their food consumption and related resource use.

**GHG Emissions

    A 2017 UCLA study found that pets in the United States alone consume about 25 to 30 percent of the calories derived from animal agriculture.

This translates to approximately 64 million tons of CO₂-equivalent emissions per year, roughly equal to the annual emissions of 13.6 million cars. This is 1% of total U.S. GHG emissions and 9% of total U.S. agricultural-sector emissions.**

Land Use

    **In the U.S., feeding dogs and cats requires about 20 to 30% of the total land used for animal agriculture. A UCLA study estimated that if pets in the U.S. were their own country, they would rank fifth in global meat consumption.

Pet food accounts for roughly 25–30% of the U.S. animal agriculture land footprint, or about 5–10% of total U.S. agricultural land use depending on how byproducts are counted.**

**Water use

      Water use varies by ingredient, but meat—especially beef—is among the most water-intensive. Producing one kilogram of beef requires approximately 15,000 liters of water. Based on the average meat consumption by U.S. pets, they are responsible for hundreds of billions of liters of virtual water use annually. A medium-sized dog may require more than 6,000 liters of water per month indirectly through its food. Pet food uses around 7 trillion liters per year, which is 4-5% of total U.S. annual freshwater withdrawals.**

**Energy use

      The U.S. total annual energy consumption is about 100 quadrillion BTUs, or approximately 105 exajoules (EJ). Pet food uses an estimated 137 million terajoules, or 0.137 EJ per year. This represents about 0.13% of total U.S. energy use. While relatively small compared to industrial and transportation sectors, it is significant for a single consumer category. This does not include the energy cost of transport, wholesale and retail operations, veterinary services, etc.**

**Summary for Food Production

GHG : 1% of total U.S. emissions. Land : 5–10% of U.S. agricultural land use. Water : 4–5.7% of total U.S. water use [depending on metric]. Energy: 0.13% of U.S. total energy use.**

Things Not included in this summary are the transport costs, manufacturing costs, infrastructure costs and the toxic chemicals used in all the above. Pet waste generates methane in landfills, and packaging materials, often plastic, add to environmental degradation. The manufacturing and disposal of pet accessories, grooming products, and toys further amplify resource use.

**Bird Mortality

     Domestic and feral cats are a major cause of bird mortality in the United States and globally. The most widely cited estimate comes from a 2013 study published in Nature Communications by scientists from the Smithsonian Conservation Biology Institute and the U.S. Fish and Wildlife Service.**

According to that study: Cats kill an estimated 1.3 to 4.0 billion birds annually in the United States.

Most of these deaths are caused by unowned (feral or loosely owned) cats, which are responsible for approximately 69% of bird kills. Owned pets allowed to roam outdoors account for the remaining share.

This scale of predation makes cats the single greatest direct human-related cause of bird mortality in North America.

Bird populations have declined sharply in North America since 1970. A 2019 study published in Science estimated a loss of nearly 3 billion birds (about 29% of total populations) over that period. While habitat loss, pesticide use, and climate change are primary drivers, cat predation is a significant additive pressure—especially on species that nest or forage on the ground.