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Identifying climate refugia is key to effective biodiversity conservation under a changing climate, especially for mountain-specialist species adapted to cold conditions and highly threatened by climate warming. We combined species distribution models (SDMs) with climate forecasts to identify climate refugia for high-elevation bird species (Lagopus muta, Anthus spinoletta, Prunella collaris, Montifringilla nivalis) in the European Alps, where the ecological effects of climate changes are particularly evident and predicted to intensify. We considered future (2041-2070) conditions (SSP585 scenario, four climate models) and identified three types of refugia: (1) in-situ refugia potentially suitable under both current and future climate conditions, ex-situ refugia suitable (2) only in the future according to all future conditions, or (3) under at least three out of four future conditions. SDMs were based on a very large, high-resolution occurrence dataset (2901-12,601 independent records for each species) collected by citizen scientists. SDMs were fitted using different algorithms, balancing statistical accuracy, ecological realism and predictive/extrapolation ability. We selected the most reliable ones based on consistency between training and testing data and extrapolation over distant areas. Future predictions revealed that all species (with the partial exception of A. spinoletta) will undergo a range contraction towards higher elevations, losing 17%-59% of their current range (larger losses in L. muta). We identified ~15,000 km2 of the Alpine region as in-situ refugia for at least three species, of which 44% are currently designated as protected areas (PAs; 18%-66% among countries). Our findings highlight the usefulness of spatially accurate data collected by citizen scientists, and the importance of model testing by extrapolating over independent areas. Climate refugia, which are only partly included within the current PAs system, should be priority sites for the conservation of Alpine high-elevation species and habitats, where habitat degradation/alteration by human activities should be prevented to ensure future suitability for alpine species. [ABSTRACT FROM AUTHOR]

Context: Tiger (Panthera tigris), leopard (Panthera pardus) and dhole (Cuon alpinus) represent a typical multi-predator system of species of conservation concern. Several studies have addressed this system, with heterogeneous results, and there's a lack of information on population dynamics of multi-species assemblages. We studied a time series (1998–2009) of abundance indices for three predators and five prey species in Bor Wildlife Sanctuary (BWS), Maharashtra, India, before it was declared as Bor Tiger Reserve (BTR) in 2009. Aims: To analyse the complex relationships within a predator–prey system in a dynamic fashion, to analyse data collected in a stable and undisturbed area and to form a comparison basis for future studies within the sanctuary after its declaration as a Tiger Reserve. Methods: A 24-h effort was made annually to census the BWS. Predators were counted at waterholes from arboreal hideouts. The prey populations were censused along 353-km line-transects. For each species, we analysed the yearly growth rate, testing the effect of inter-species abundance. Key results: Tiger growth rate did not depend on any particular prey, whereas mesopredators seemed to depend on medium-sized prey. A die-out of dholes in 2001 was followed by an increase in tiger populations (from 4 to 11), which, in turn, negatively affected leopard numbers (from 6 to 2).We found no direct evidence of top-down effect, but the density dependence for three of five prey species could be linked to predation pressure. We found some evidence of interspecific competition among prey species, especially among ungulates, potentially being mediated by predation pressure. Conclusions: The relationships among species in a predator–prey system are very complex and often could be explained only by more-than-two-species interactions. The disappearance of one predator, not necessarily the top predator, could bring multiple effects, for which it could be difficult to detect causal relationships. Implications: All subsequent changes in human activities in the sanctuary, as a consequence of its designation as the BTR in 2009, should be evaluated with respect to the results of the present study. The conservation of large predators should rely on the maintenance of a rich and abundant prey base, in which different-sized prey could lessen interactive-competition among the predators. We analysed a time series comprising abundance data for a predator–prey system composed by tiger, leopard and dhole, and five prey species: sambar, nilgai, chital, wild boar, and Hanuman langur monkey. Photograph by Swapnil Khumbhojkar. [ABSTRACT FROM AUTHOR]

The greatest loss of biodiversity in the EU has occurred on agricultural land. The Common Starling (Sturnus vulgaris) is one of the many numerous and widespread European farmland breeding bird species showing major population declines linked to European agricultural intensification. Here we present results based on monitoring data collected since 1975 in 24 countries to examine the influence of changing extent of grassland and cattle abundance (based on results of earlier studies showing the importance of lowland cattle grazed grassland for the species), wintering provenance and temperature on national breeding population trends of Starlings across Europe. Positive Starling population trends in Central-East Europe contrast with negative trends in North and West Europe. Based on this indicative approach, we found some support for the importance of cattle stock and no support for grassland, temperature or wintering provenance to explain Starling population trends in Europe. However, we acknowledge such a European-wide analysis may conceal regional differences in responses and suggest that currently accessible national land use datamight be insufficient to describe the detailed current changes in animal husbandry and grassland management that may be responsible for changes in food availability and hence breeding Starling abundance and their differences across Europe. Reviewing results from local studies relating Starling population trends to local agricultural change offer contradictory results, suggesting complex interacting processes at work. We recommend combining national datasets on demography, land-use/agricultural practices and from autecological research to better explain the reasons for contrasting Starling trends across Europe, to enable us to predict how changing agriculture will affect Starlings and potentially suggest mitigation measures to restore local populations where possible. [ABSTRACT FROM AUTHOR]

We studied the Little Owl Athene noctua distribution in the city of Milan with a single-visit survey carried out during the 2013 breeding season. We searched for Little Owls in 82 sampling stations spread out all over the city using play-back technique. We detected 52 Little Owls in 33 sampling stations. The species appeared to be quite common in the municipality of Milan but with a greater abundance in the southern outskirts (Parco Agricolo Sud Milano). We modelled species occurrence by means of Generalized Additive Models selecting our best models with an information-theoretic approach. Little Owls' presence resulted more likely in presence of permanent crops and farmsteads. The latter represent one of the main sources of nesting sites for the species. Little Owl's detection is also more likely in relation with buildings' mean height, of about 10 meters while it appears to avoid completely the more dense urban areas present in the central and in the north-eastern side of Milan. The Little owl is finally more likely to be found in the larger urban parks. The species' distribution in the study area showed a significant spatial autocorrelation. Our best model accurately predicts 80.2% of observed data. According to model predictions 29.5% of the municipal territory has a medium or medium-high habitat suitability for the Little Owl. Field methods used in this work seemed to be easily carried out even by non-professionals. We discussed the global survey protocol for the species in light of our experience and with the desirable outlook of a large scale monitoring programme in our country: this is urgently needed to fill in the gap of knowledge on large scale distribution and population trends of the Little owl. [ABSTRACT FROM AUTHOR]

Mountain areas often hold special species communities, and they are high on the list of conservation concern. Global warming and changes in human land use, such as grazing pressure and afforestation, have been suggested to be major threats for biodiversity in the mountain areas, affecting species abundance and causing distribution shifts towards mountaintops. Population shifts towards poles and mountaintops have been documented in several areas, indicating that climate change is one of the key drivers of species' distribution changes. Despite the high conservation concern, relatively little is known about the population trends of species in mountain areas due to low accessibility and difficult working conditions. Thanks to the recent improvement of bird monitoring schemes around Europe, we can here report a first account of population trends of 44 bird species from four major European mountain regions: Fennoscandia, UK upland, south‐western (Iberia) and south‐central mountains (Alps), covering 12 countries. Overall, the mountain bird species declined significantly (−7%) during 2002–2014, which is similar to the declining rate in common birds in Europe during the same period. Mountain specialists showed a significant −10% decline in population numbers. The slope for mountain generalists was also negative, but not significantly so. The slopes of specialists and generalists did not differ from each other. Fennoscandian and Iberian populations were on average declining, while in United Kingdom and Alps, trends were nonsignificant. Temperature change or migratory behaviour was not significantly associated with regional population trends of species. Alpine habitats are highly vulnerable to climate change, and this is certainly one of the main drivers of mountain bird population trends. However, observed declines can also be partly linked with local land use practices. More efforts should be undertaken to identify the causes of decline and to increase conservation efforts for these populations. Overall populations of 44 mountain bird species declined significantly c. −7% in Europe (inc. Fennoscandia, UK upland, Alps and Iberia) during 2002–2014. Mountain specialists species, which occur only in the mountain areas in Europe, showed a significant −10% decline in population numbers. [ABSTRACT FROM AUTHOR]