Pastoralism in Old World savannas is known to emit a significant share of global livestock-sourced greenhouse gases (GHG). Here, we compare calculated emissions from animals in a wildlife-dominated savanna (14.3 Mg km−2), to those in an adjacent land with similar ecological characteristics but under pastoralism (12.8 Mg km−2). The similar estimates for both, wildlife and pastoralism (76.2 vs 76.5 Mg CO2-eq km−2), point out an intrinsic association of emissions with herbivore ecological niches. Considering natural baseline or natural background emissions in grazing systems has important implications in the analysis of global food systems.