Large herbivores have significant impacts on ecosystem structure and functioning throughout Earth's biomes (Enquist et al., 2020;Kristensen et al., 2022;Lundgren et al., 2020). During the Pleistocene, land in the non-glaciated high latitudes supported a diverse assemblage of large herbivores, including mammoth, woolly rhino, and wild horse, that grazed on a productive graminoid-and forb-rich heterogeneous vegetation matrix and likely maintained it through selective foraging, increased nutrient cycling, bark-stripping, and trampling (Macias-Fauria et al., 2020;Olofsson & Post, 2018;Zimov et al., 2012). In the modern moss-and shrub-dominated Arctic tundra, reindeer (Rangifer tarandus L.) are the only remaining large herbivores still widespread (Olofsson & Post, 2018). Local-scale studies, utilizing variations in grazing intensity due to the introduction of reindeer on islands (