Environmental impacts of food consumption by companion dogs and cats in Japan

In Japan, there are more than 20 million companion dogs and cats that consume resources. Yet, little is known about their environmental impacts and the related energy policies aiming to reduce such impacts. In this study, we quantified Japanese companion dogs and cats' environmental impacts regarding their food consumptions. More specifically, we analyzed their dietary "ecological paw print" (EPP), greenhouse gas (GHG) emissions and energy consumption. Our results showed that the dietary EPP of an average-sized dog was 0.33-2.19 ha per year, which was equivalent to one Japanese people's dietary "ecological footprint" (EF) in a year. The dietary EPP of an average-sized cat was lower with 0.32-0.56 ha per year. All companion dogs and cats in Japan could consume about 3.6-15.6% of the amount of food that Japanese people do and release 2.5-10.7 million tons of GHG through their diet in a year. Many companion animals (particularly medium-sized and large dogs) consumed more energy than they actually needed to sustain their normal activity. By providing direct data on food consumption, this study gained an insight into the future of possible energy policies to reduce Japanese companion animals' environmental impacts.