Rhys Lemoine from the Pleistocene Rewilding and Wildlife Conservation Facebook group has posted the following thoughts about what constitutes a useful baseline for rewilding going forward, given current and projected climatic changes and habitats. I agree with him.
When we think about the Pleistocene, and by extension Pleistocene Rewilding, we tend to think of the very end of that era, roughly 14 thousand years ago. However, for the purposes of animal reintroductions, this is not a very useful baseline. The Earth was much colder then and various animals would have had different distributions than today. This being considered, many choose to use the early Holocene as a more realistic baseline. However, the Holocene was massively influenced by human activity, and had a comparatively sparse megafaunal assemblage. I therefore believe a better baseline would be the Eemian period, roughly 100-150 thousand years ago. This period was at times slightly hotter and wetter than today, with higher sea levels, but otherwise had very similar plant and animal communities. It is also worth noting that our current climate may be rapidly heading towards similar conditions. The Eemian is technically a European term, with that particular interglacial having different names elsewhere. As an example I’m going to discuss the Eemian fauna of northwest Europe, including Holland, Germany, Denmark, England, Belgium, and France. At the time, this area consisted of mixed forest, grasslands, heaths, and wetlands, similar to the conditions present today. Many of the megafauna were typical Holocene species, including Elke (Alces alces), Red Deer (Cervus elephas), Roe Deer (Capreolus capreolus), Fallow Deer (Dama dama), Aurochs (Bos taurus), Wild Boar (Sus scrofa), and Wild Horse (Equus caballus). There were woodland bison (Bison schoetensacki), which have been recently determined to be very similar to today’s wisents (Bison bonasus). There were also water buffalo (Bubalus murrensis), wild ass (Equus hemionus), and large, thick-skinned herbivores, including elephants (Palaeoloxodon antiquus), hippopotamus (Hippopotamus amphibius), and two species of rhinoceros (Stephanorhinus hemitoechus and kirchbergensis). Large predators included the wolves (Canis lupus) and brown bears (Ursus arctos) typical of Europe today, as well as lions (Panthera leo), leopards (Panthera pardus), hyenas (Crocuta crocuta and Hyaena hyaena), and black bears similar to those now found in eastern Asia (Ursus thibetanus). What’s interesting, and rather refreshing for our line of research, is that all of these species have modern relatives and equivalents in Europe or elsewhere, which could be introduced to the area to recreate a similar ecosystem. An Eemian Rewilding park could potentially be very productive and profitable, while sustaining greater biodiversity. It would also be an excellent reintroduction site for smaller animals that have disappeared from Europe since Pleistocene times such as Dholes (Cuon alpinus) and Desmans (Desmana moschatus). In any case, I would love to know what you think. I think we may be divided on which proxies would best for certain species, but I think we can all agree that proxies do exist, with the exception of three species; Megaloceros, Homotherium, and Machairodus. Cheers.