Adapt or die—Response of large herbivores to environmental changes in Europe during the Holocene

Abstract

Climate warming and human landscape transformation during the Holocene resulted in environmental changes for wild animals. The last remnants of the European Pleistocene megafauna that survived into the Holocene were particularly vulnerable to changes in habitat. To track the response of habitat use and foraging of large herbivores to natural and anthropogenic changes in environmental conditions during the Holocene, we investigated carbon (δ13C) and nitrogen (δ15N) stable isotope composition in bone collagen of moose (Alces alces), European bison (Bison bonasus) and aurochs (Bos primigenius) in Central and Eastern Europe. We found strong variations in isotope compositions in the studied species throughout the Holocene and diverse responses to changing environmental conditions. All three species showed significant changes in their δ13C values reflecting a shift of foraging habitats from more open in the Early and pre‐Neolithic Holocene to more forest during the Neolithic and Late Holocene. This shift was strongest in European bison, suggesting higher plasticity, more limited in moose, and the least in aurochs. Significant increases of δ15N values in European bison and moose are evidence of a diet change towards more grazing, but may also reflect increased nitrogen in soils following deglaciation and global temperature increases. Among the factors explaining the observed isotope variations were time (age of samples), longitude and elevation in European bison, and time, longitude and forest cover in aurochs. None of the analysed factors explained isotope variations in moose. Our results demonstrate the strong influence of natural (forest expansion) and anthropogenic (deforestation and human pressure) changes on the foraging ecology of large herbivores, with forests playing a major role as a refugial habitat since the Neolithic, particularly for European bison and aurochs. We propose that high flexibility in foraging strategy was the key for survival of large herbivores in the changing environmental conditions of the Holocene.

European bison conservation must move beyond entrenched debates – response to Kerley et al. (2020)

“…All recent studies of European bison habitat use we know of suggest that European bison are neither a strict forest specialist nor a strict grassland specialist. For example, European bison have exhibited intermediate diets between true grazers and true browsers, along with high diet plasticity, throughout the Holocene (Bocherens et al ., 2015; Hofman‐Kamińska et al ., 2019), a pattern also found in contemporary herds (Krasińska et al ., 2014). Vegetation reconstructions (Kuemmerle et al ., 2012a) and paleozoological data (Benecke, 2005) suggest that European bison have, for at least 8000 years, been associated with landscapes containing a considerable amount of forest alongside open areas – as they are today (Kuemmerle et al ., 2011; Kuemmerle et al ., 2018).…”

“…All recent studies of European bison habitat use we know of suggest that European bison are neither a strict forest specialist nor a strict grassland specialist. For example, European bison have exhibited intermediate diets between true grazers and true browsers, along with high diet plasticity, throughout the Holocene(Bocherens et al, 2015;Hofman-Kami nska et al, 2019), a pattern also found in contemporary herds(Krasi nska et al, 2014). Vegetation reconstructions…”

European pollen-based REVEALS land-cover reconstructions for the Holocene: methodology, mapping and potentials

“…This in turn allows us to consider when environmental changes moved beyond the envelope of natural variability (Ruddiman, 2003;Ruddiman et al, 2016). We focus here on the role of LULCC in the climate system; anthropogenic land-cover change can have broader consequences on other processes and changes, such as erosion and fluvial systems (Downs and Piégay, 2019), biodiversity loss (Barnosky et al, 2012), nutrient cycling (Guiry et al, 2018;McLauchlan et al, 2013), habitat exploitation by megafauna (Hofman-Kamińska et al, 2019) and wider ecosystem functioning (Ellis, 2015;Stephens et al, 2019).…”

Ancient Faunal History Revealed by Interdisciplinary Biomolecular Approaches

“…Attempts to reconstruct the past diet and behaviour of prehistoric bison have to date, for the most part, been conducted as separate biogeochemical studies (e.g., [130,[147][148][149][150]). Without diminishing their significant scientific contribution, we argue that interdisciplinary studies that integrate morphological, isotopic, dietary, and genetic data would contextualise and enhance our knowledge of this enigmatic species complex.…”