Overlooked effects of temporal resolution choice on climate-proof spatial conservation plans for biodiversity

Global changes require conservation planners to integrate environmental dynamics into their strategies. Forward-looking species-based conservation plans typically use data for a few time periods (ten to thirty years apart) to pinpoint the adaptive areas providing the conditions for species to follow their suitable climates and persist. With such gaps in time, species' responses to environmental conditions between the evaluated periods are not addressed. Here we test whether choices on the temporal resolution in analysis (length of time in between time slices) impact the location and perceived effectiveness of the resulting climate-adaptive areas and the value of established protected areas in providing ground for the spatial responses of species. We address these issues using a conservation exercise set up in Western France, where ten vertebrate species are targeted for persistence in the long term (i.e., 2050). For each species, the area prioritization solutions obtained by using three settings of temporal resolution (annual, decadal and tri-decadal) were largely dissimilar. The climate adaptive areas obtained with annual data defined convoluted adaptive trajectories, largely distinct from the trajectories achieved with decadal and tri-decadal data. This has reflections on the perceived effectiveness of established protected areas in encompassing those adaptive trajectories. In the final stages of planning, conservation planers need to provide rigorous proposals for the establishment of effective conservation actions. This study pinpoints the need for fine-resolute temporal data to reach such effectiveness in the design of climate-proof protected area networks.