A new study has found that wild ruminants, including deer, moose, and llamas, contribute to atmospheric methane levels. Researchers calculated that these animals release approximately 3 million tonnes of methane annually.
More than half of this methane is attributed to just six species of deer. The study, published in the Journal of Geophysical Research: Biogeosciences, combined global wild animal population estimates with methane emission estimates based on body mass and diet.
Theresia Yazbeck from the Max Planck Institute for Biogeochemistry in Jena, Germany, and colleagues conducted the research. While wild ruminants contribute to methane emissions, their total input is considered minuscule compared to the over 600 million tonnes of annual global methane emissions, being about 38 times less than that from domesticated livestock.