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Biotic interactions are expected to influence species’ responses to climate change, but they are usually not included when predicting future range shifts. We assessed the importance of biotic interactions to understand future consequences of climate and land use change for biodiversity using as a model system the brown bear (Ursus arctos) in Europe. By including biotic interactions using the spatial variation of energy contribution and habitat models of each food species, we showed that the use of biotic factors considerably improves our understanding of the distribution of brown bears. Predicted future range shifts, which included changes in the distribution of food species, varied greatly when considering various scenarios of change in biotic factors, warning about future indirect climate change effects. Our study confirmed that advancing our understanding of ecological networks of species interactions will improve future scenarios of biodiversity change, which is key for conserving biodiversity and ecosystem services.

Road networks provide several benefits to human societies; however, they are also one of the major drivers of fragmentation and habitat degradation. Their negative effects include wildlife-vehicle collisions which are associated with increased barrier effects, restricted gene flow, and increased local extinction risk. Large carnivores, such as the brown bear (Ursus arctos), are vulnerable to road mortality while they also put human safety at risk in every collision. We recorded approximately 100 bear-vehicle collisions during the last 15 years (2005–2020) in northwestern Greece and identified common aspects for collisions, i.e., spatial, or temporal segregation of collision events, road features, and age or sex of the involved animals. We recorded collisions in both the core distribution area of brown bears, as well as at the periphery, where few individuals, mostly males, disperse. According to our findings, there are four collision hotspots which include ca. 60% of total collisions. Bear-vehicle collisions occurred mostly in periods of increased animal mobility, under poor light conditions and low visibility. In most cases, we deem that a collision was unavoidable at the time of animal detection, because the driver could not have reacted in time to avoid it. Appropriate fencing, in combination with the retention of safe passages for the animals, can minimize collisions. Therefore, such mitigation measures, wildlife warning signs and other collision prevention systems, such as animal detection systems, should be adopted to decrease the number of bear-vehicle collisions and improve road safety.

Background Exploring species richness and turnover patterns and their drivers can provide new insights into underlying mechanisms shaping community assembly, with significant implications for biodiversity conservation. Here, we explored diversity patterns of non-endemic, neo-endemic and palaeo-endemic vascular plants in Crete, Greece, a Mediterranean hotspot of plant richness and endemism. We evaluated the relationship between α-diversity and environmental (bioclimatic variables, topography), and anthropogenic variables by Generalized Additive Models, after accounting for spatial autocorrelation. Then, we quantified turnover using the novel concept of zeta diversity (the number of shared species by multiple sites), a framework which allows to explore the full spectrum of compositional turnover, the contribution of rare and widespread species to observed patterns and the underlying processes shaping them. Finally, we explored the abiotic and biotic effects, i.e. how well one category of species (non-endemics, palaeo-endemics, neo-endemics) predicts the patterns of the other categories, on zeta diversity by multi-site Generalized Dissimilarity Modelling. Results We found a strong correlation between neo-endemic and palaeo-endemic α-diversity, with climate, topography, and human impact driving species richness. Zeta diversity analysis revealed a sharper decrease of shared palaeo-endemic species, followed by neo-endemics, and then by non-endemics with the number of sites considered to estimate compositional turnover. Perhaps, the narrow distributions of palaeo-endemics as relict species and often habitat specialists, thus persisting locally, and of neo-endemics that may have not reached yet their potential geographical range, resulted in the observed zeta diversity decline pattern. Deterministic processes controlled species turnover of rare non-endemic and neo-endemic species, while deterministic and stochastic processes contributed similarly to palaeo-endemic turnover. However, stochasticity dominates in the case of widespread species in all occasions. The environmental and anthropogenic variables were poor predictors of compositional turnover, especially of widespread species. However, the non-endemic species composition was correlated to rare palaeo-endemics and neo-endemics, highlighting the importance of biotic effects in driving turnover patterns. Conclusions It seems that centers of neo-endemism of vascular plants coincide with centers of palaeo-endemism in Crete, but species richness and species turnover are shaped by different drivers.

The striped hyena (Hyaena hyaena Linnaeus, 1758) is one of the large carnivores of forest and grassland ecosystems across Africa and Asia and is currently threatened throughout its range. Hyena habitats are shrinking, due to the increase of human-dominated landscapes. The aim of this study was to identify hyena habitat use as indicated by visitation frequency in the human-dominated landscape of lowland Nepal. We followed a camera trap protocol for the estimation of hyena presence and visitation frequency. We used a generalized additive modelling approach with zero-inflated Poisson distribution to evaluate the effects of environmental variables on capture frequency. Our results showed that the two most important and significant predictors of hyena frequency data were canopy volume and maxD (the maximum among the shortest distances to water sources, agriculture land and villages). The highest hyena frequencies were in sites with low canopy volume, i.e. riverbeds and grasslands, whereas lower frequencies were observed in dense forests, i.e. acacia and riverine forests. Additionally, hyena frequency increased with increasing maxD up to 5–6 km and then dropped sharply at larger maxD values. Overall, our study suggests that hyenas prefer open landscapes along rivers and human settlements, where the following combination of conditions is met: adequate cover, access to food and water. The preservation of natural open landscapes close to human settlements and rugged hilly areas seems crucial for the long-term conservation of hyenas.

Land use change poses as the top threat for biodiversity decline, and road sprawl as a key driver behind it globally. According to the recent Landscape Fragmentation Indicator (LFI), Greece is less fragmented than the rest of Europe but presents higher rates of fragmentation increase. We developed the Roadless Fragmentation Indicator (RFI) to monitor fragmentation in more natural ecosystems. The RFI calculates the percentage of land that is covered by roadless areas (RAs), defined as land patches over 1 km2 that are over 1 km away from the nearest road. We produced the roadless map of Greece, concluding to 1115 RAs ranked by size (1–256 km2) and to a national RFI of less than 5%. The RFI reflected naturalness, was significantly higher in the Natura 2000 network, and was more sensitive in less fragmented zones. Six mountains (0.51% of Greek land) have remained largely roadless (RAs ≥ 50 km2) and should be protected as such. We call for a straightforward roadlessness policy under a “European Roadless Rule” that would legally protect at least 2% of European land as road-free area. We also call for no further unjustified road sprawl in more natural and least fragmented ecosystems, as a measure to be integrated in all sectors of EU policy and particularly in the spatial planning of development projects. We recommend a five-step roadlessness guideline to be implemented in the European Union, including Greece, as a measure to effectively address biodiversity decline.

Protected Areas are a main conservation tool to halt biodiversity loss. However, their performance has been often questioned and the need to improve their effectiveness is now more apparent than ever. Here, we propose Roadless Areas as a conservation target to increase the cover and effectiveness of Protected Areas. Roadless Areas represent natural and semi-natural areas of high conservation value that have no or little traffic and provide multiple ecosystem services. Here, we develop a methodological framework to identify Roadless Areas in Europe and assess their spatial properties and conservation status. We examine how the European Union’s conservation network, Natura 2000, would expand if Roadless Areas that are already partially included in Natura 2000 terrestrial sites or are adjacent to them would be added to the existing conservation network. We find that European lands are highly fragmented. Roadless Areas are unevenly distributed, and cover more than 30% of the European Union territory, with large Roadless Areas (≥100 km2) occupying about 18% of that surface. At the national level, there is a large variation in the percentage of overlap between Natura 2000 sites and Roadless Areas, with the Natura 2000 network currently encompassing between 19% and 89% of the Roadless Areas surface, depending on the member state. Our results demonstrate that Roadless Areas adjacent to Natura 2000 sites cover > 65% of the total Natura 2000 surface. As Roadless Areas have limited human access, we suggest integrating Roadless Areas into biodiversity conservation networks as a timely solution to minimize conflicts over expanding Protected Areas in the European Union and to achieve the goals of the European Union’s 2020 Biodiversity Strategy.

Elevational gradients provide a unique opportunity to explore species responses to changing environmental conditions. Here, we focus on an elevational gradient in Crete, a climate-vulnerable Mediterranean plant biodiversity hotspot and explore the diversity patterns and underlying mechanisms of different plant life forms. We found that the significant differences in life forms&rsquo, elevational and environmental ranges are reflected in &alpha, diversity (species richness at local scale), &gamma, diversity (species richness at regional scale) and &beta, diversity (variation in species composition). The &alpha, and &gamma, diversity decreased with elevation, while &beta, diversity followed a hump-shaped relationship, with the peak varying between life forms. However, &beta, deviation (deviation from null expectations) varied significantly with elevation but was life formindependent. This suggests that species composition is shaped by the size of the available species pool which depends on life form, but also by other deterministic or stochastic processes that act in a similar way for different life forms. The strength of these processes varies with elevation, with hotter&ndash, drier conditions and increased human activities filtering species composition at lowlands and large-scale processes determining the species pool size overriding local ecological processes at higher elevations.