A recent scientific review claims that the European bison (Bison bonasus) should not be used under any circumstances in the Iberian Peninsula (https://doi.org/10.1111/csp2.13221). A group of scientists from different institutions in Spain, Czech Republic, Poland, Sweden and Netherlands, including members of our Animal Physiology and Behaviour team, challenge these claims, since such a definitive conclusion is not supported by conclusive evidence and risks prematurely closing an important, ongoing scientific debate. Such a topic was recently discussed within the Iberian Society for the Conservation and Study of Mammals (SECEM), which also concluded that further scientific evidence is needed before clear conclusions can be drawn.
In our reply, just published in Conservation Science and Practice (https://doi.org/10.1111/csp2.70132), we highlight that the current fossil record is too limited and uncertain to determine whether European bison were historically absent from Iberia. Importantly, recent paleontological findings from Navarra suggest the presence of Bison bonasus in Northern Iberia. Although still under investigation, these results reinforce the view that the species' historical distribution remains unresolved and that firm conclusions are premature. We also question assumptions about the ecological unsuitability and dispersal barriers. Rather than arguing for or against reintroduction per se, we emphasise that decisions should be based on robust, interdisciplinary evidence, integrating palaeontology, ecology, field data, and a deeper understanding of the current anthropised landscapes.
The role of European bison in Spain remains an open scientific question, and continued research, rather than categorical rejection, is essential to inform conservation and rewilding strategies properly. In the current context of climate change, biodiversity loss, and the new EU directive promoting the restoration of ecosystems, we need a relaxed yet accurate debate, not dogmatism.
Bartolomé J, Cassinello J, Ceacero F, Klich D, Komárková M, Lemoine RT, van der Made J, Morán F, Olech W, Palau J, Perzanowski K, Rodríguez E (2026). Comment: Nores et al. (2024) fail in their attempt to demonstrate the inappropriateness of an eventual introduction of the European bison to Spain as a rewilding initiative. Conservation Science & Practice, 2026:e70132. https://doi.org/10.1111/csp2.70132