Okin GS (2017) Environmental impacts of food consumption by dogs and cats. PLoS ONE 12(8): e0181301. https://doi.org/10.1371/journal.pone.0181301

“In the US, there are more than 163 million dogs and cats that consume, as a significant portion of their diet, animal products and therefore potentially constitute a considerable dietary footprint. Here, the energy and animal-derived product consumption of these pets in the US is evaluated for the first time, as are the environmental impacts from the animal products fed to them, including feces production. In the US, dogs and cats consume about 19% ± 2% of the amount of dietary energy that humans do..They produce about 30% ± 13%, by mass, as much feces as Americans..and through their diet, constitute about 25–30% of the environmental impacts from animal production in terms of the use of land, water, fossil fuel, phosphate, and biocides. Dog and cat animal product consumption is responsible for release of up to 64 ± 16 million tons CO₂-equivalent methane and nitrous oxide, two powerful greenhouse gasses (GHGs). Americans are the largest pet owners in the world, but the tradition of pet ownership in the US has considerable costs. As pet ownership increases in some developing countries, especially China, and trends continue in pet food toward higher content and quality of meat, globally, pet ownership will compound the environmental impacts of human dietary choices. Reducing the rate of dog and cat ownership, perhaps in favor of other pets that offer similar health and emotional benefits would considerably reduce these impacts. Simultaneous industry-wide efforts to reduce overfeeding, reduce waste, and find alternative sources of protein will also reduce these impacts.” [All of us who have companions animals in our homes must proactively engage in seeking viable alternative food products for them [there are many healthy grain and vegetable based food products for cats, dogs and humans). We make decisions each day that impact our environment – the choice to use and discard products in every form (plastic, cardboard) and to consume animals based foods must pivot to alternative diets. The research continues to elucidate unavoidable facts- as inconvenient as they are, the truth requires us to change, for the future lives of humans, animals, and all other species. Stepping off tiny soap box.]