Temporary ponds in peninsular Spain: insights for the conservation of a threatened habitat under global change

Abstract

Wetlands are recognized as threatened habitats in Europe, having largely disappeared globally because of ongoing anthropogenic pressures. Particularly, temporary ponds are priority habitats for conservation in the Mediterranean region, yet they require urgent actions due to their vulnerability to climate change and external perturbations. However, large-scale impacts of agricultural intensification and climate effects on temporary ponds remains poorly understood, as their small size and shallow depth make them particularly challenging to monitor using remote sensing techniques. In peninsular Spain, we assessed (1) the legal protection status of 1303 ponds from 193 bibliographic, and public sources, quantifying overlaps between the Natura 2000 network (N2K) and other Protected Areas (PAs), (2) how protection status influences the occurrence of visible anthropogenic impacts, and (3) recent trends in water occurrence by modelling climatic variables and these anthropogenic impacts. Google Earth Pro imagery was used to record the presence of surface water and these impacts. Our results revealed substantial overlap between N2K and other PAs. N2K alone was less effective in mitigating agricultural impacts. Ponds under overlapping designations of N2K and other PAs showed lower prevalence of impacts. Agriculture-related impacts—i.e. ploughed borders, ploughed basin, and channelling—were the most widespread and associated with pond disappearance among visually observable impacts. Ploughed basin, channelling, and climatic drivers altered pond hydroperiods and accelerated habitat loss. These findings highlight the importance of effective protection, underscoring the urgent need to strengthen management within existing PAs, expand conservation to unprotected ponds, and integrate cost-effective monitoring for early detection of degradation.