Nationwide ranger-based survey reveals the widespread decline of the Iberian rabbit (Oryctolagus cuniculus algirus) in Spain

Scientists increasingly recognize the importance of evolutionary-based conservation strategies to better protect biodiversity, emphasizing that population units that diverged long ago may warrant priority for conservation and distinct management as Evolutionary Significant Units (ESUs). In the European rabbit ( Oryctolagus cuniculus ), two ESUs became geographically isolated around two million years ago in their native area in the Iberian Peninsula. Oryctolagus cuniculus algirus (Oca) and Oryctolagus cuniculus cuniculus (Occ) now occur mostly in separate regions, with limited overlap in a narrow contact zone in Spain. We present robust evidence of a widespread decline of Oca, based on a nationwide online survey of environmental rangers across mainland Spain. A total of 1,956 rangers working throughout Spain answered the survey (response rate: 39.8%). Within the Oca range, 70.6% of participants reported decreasing trends. In contrast, 53.6% of participants within the Occ range reported increasing or stable trends. These findings suggest that Oca faces a concerning conservation status, underscoring the urgent need to preserve this ESU, which is restricted to Portugal, western Spain, some areas of North Africa and a few Atlantic islands. We recommend that Spain’s unified management framework for both lineages be replaced with different management models tailored to the specific needs of each ESU. This would enable more efficient conservation of Oca, and context-specific management of Occ, while reducing social conflicts over rabbit management. Additionally, translocations of Occ rabbits into the distribution area of Oca should be urgently prohibited to prevent replacement of the latter by the former.