2026/04/29 by José M. Fedriani, Pedro J. Garrote, Brayan Morera +6 · 1 voice
Environmental Science · #Animal Ecology and Behavior Studies #Ecology and Vegetation Dynamics Studies #Wildlife Ecology and Conservation
paper · doi:10.1016/j.biocon.2026.111873
openalex created_date 2025/12/06 · openalex publication_date 2026/04/29 · openalex updated_date 2026/07/15
Long-lived tree species can undergo decades of unnoticed demographic erosion before population collapse becomes evident, making it essential to evaluate whether protected areas effectively mitigate these processes. To assess this, we compared the demographic performance of the Iberian pear (Pyrus bourgaeana) across five populations located inside and outside Doñana National Park (SW Spain). Using cross-sectional surveys and two decades of demographic monitoring, we quantified seedling emergence and mortality, sapling abundance and browsing, and adult survival. Seedling emergence occurred almost exclusively beneath adult trees, and survival was extremely low (<12%), driven mainly by herbivory (especially inside the Park) and by desiccation. Sapling browsing pressure was greater within (40-23%) than outside the Park (27-14%). Adult mortality varied sharply among sites, peaking in Matasgordas, a core Park location where over 60% of adults died within two decades, coinciding with severe groundwater decline and virtually no recruitment into reproductive stages. These findings expose a conservation paradox: while National Park status prevents land-use conversion, it simultaneously allows high ungulate densities and remains vulnerable to regional groundwater overexploitation and prolonged drought. Together, these pressures suppress regeneration and accelerate adult mortality, pushing populations toward collapse despite formal protection. Our results indicate that current management is insufficient to ensure the persistence of the Iberian pear and likely other tree species in Doñana ’s scrublands. Effective conservation will require securing sustainable groundwater use, regulating herbivore densities, and restoring functional dispersal processes, and should prompt a reassessment of the species’ conservation status.