Summary 1. Freshwater conservation has received less attention than its terrestrial or marine counterparts. Given the accelerated rate of change and intensive human use that freshwater ecosystems are submitted to, it is urgent to focus more attention on fresh waters. Existing conservation planning tools – such as Marxan – need to be modified to account for the special nature of these systems. Connectivity plays a key role in freshwater ecosystems. Threats are mediated along river corridors, and the condition of the entire catchment influences river biodiversity downstream. This needs to be considered in conservation planning. 2. The probabilities of occurrence of nine native freshwater fish species in a Mediterranean river basin, obtained from Multivariate Adaptive Regression Splines‐ Generalized Linear Model (MARS‐GLM) models, were used as features to develop spatial conservation priorities. The priorities accounted for complementarity and spatial design issues. 3. To deal with the connected nature of rivers, we modified Marxan’s boundary length penalty, avoiding the selection of isolated planning units and forcing the inclusion of closer upstream areas. We introduced ‘virtual boundaries’ between non‐headwater stream segments and added distance‐weighted penalties to the overall connectivity cost (CP) when stream segments upstream of the selected planning units are not selected. 4. This approach to prioritising connectivity is concordant with ecological theory, as it considers the natural and roughly exponential decay of upstream influences with distance. It accounts for the natural capacity of rivers to mitigate impacts when designing reserves. When connectivity was not emphasised, Marxan prioritised natural corridors for longitudinal movements. In contrast, whole sub‐basins were prioritised when connectivity was emphasised. Changing the relative emphasis on connectivity substantially changed the spatial prioritisation; our conservation investment could move from one basin to another. 5. Our novel approach to dealing with directional connectivity enables managers of freshwater systems to set ecologically meaningful spatial conservation priorities.

Fire has been a source of global biodiversity for millions of years. However, interactions with anthropogenic drivers such as climate change, land use, and invasive species are changing the nature of fire activity and its impacts. We review how such changes are threatening species with extinction and transforming terrestrial ecosystems. Conservation of Earth’s biological diversity will be achieved only by recognizing and responding to the critical role of fire. In the Anthropocene, this requires that conservation planning explicitly includes the combined effects of human activities and fire regimes. Improved forecasts for biodiversity must also integrate the connections among people, fire, and ecosystems. Such integration provides an opportunity for new actions that could revolutionize how society sustains biodiversity in a time of changing fire activity.

Abstract. Mediterranean endemic freshwater fish are among the most threatened biota in the world. Distinguishing the role of different extinction drivers and their potential interactions is crucial for achieving conservation goals. While some authors argue that invasive species are a main driver of native species declines, others see their proliferation as a co-occurring process to biodiversity loss driven by habitat degradation. It is difficult to discern between the two potential causes given that few invaded ecosystems are free from habitat degradation, and that both factors may interact in different ways.Here we analyze the relative importance of habitat degradation and invasive species in the decline of native fish assemblages in the Guadiana River basin (southwestern Iberian Peninsula) using an information theoretic approach to evaluate interaction pathways between invasive species and habitat degradation (structural equation modeling, SEM). We also tested the possible changes in the functional relationships between invasive and native species, measured as the per capita effect of invasive species, using ANCOVA.We found that the abundance of invasive species was the best single predictor of natives' decline and had the highest Akaike weight among the set of predictor variables examined. Habitat degradation neither played an active role nor influenced the per capita effect of invasive species on natives. Our analyses indicated that downstream reaches and areas close to reservoirs had the most invaded fish assemblages, independently of their habitat degradation status. The proliferation of invasive species poses a strong threat to the persistence of native assemblages in highly fluctuating environments. Therefore, conservation efforts to reduce native freshwater fish diversity loss in Mediterranean rivers should focus on mitigating the effect of invasive species and preventing future invasions.