Scientists at the Weizmann Institute in Israel determined the biomass of livestock and found that it is several dozen times greater than the mass of all wild land mammals. The results of the study are published in the journal Proceedings of the National Academy of Sciences (PNAS).
The team analyzed available data on the total abundance (number of individuals) of several hundred mammal species and used it to build a model to derive the total biomass of terrestrial mammal species for which global abundance is unknown. It is estimated that the mass of all terrestrial wild mammals is 20 million tons, that is, approximately three kilograms for every person on Earth.
Large herbivores such as white-tailed deer, wild boar and African elephant have been found to be the main contributors to the biomass of wild land mammals. In addition, artiodactyl mammals such as deer and wild boars make up about half of the total mass of terrestrial wild mammals. The total biomass of wild marine mammals is estimated at 40 million tons, and baleen whales account for half.
The total mammalian biomass is dominated by livestock, whose mass reaches 630 million tons, and humans, with a total mass of 390 million tons. However, human influence also strongly determines the abundance of some wild mammals, since white-tailed deer and wild boars have been introduced to many parts of the world.