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Abstract: A field based technique has been developed to identify and delineate the areas of potential hill slope instability with the help of ecological indicator. Habitat characteristics and spatial–temporal occurrence of indicator taxon were investigated with respect to its natural environment. The study includes extensive field surveys, laboratory studies and comparison of historical maps at local scale coupled with literature appraisal at local, regional and global scales. Instability generated due to slope disturbances by natural and anthropogenic activities along the roads, ravines, stream banks, terraces, cultivated land, old landslide sites and human settlements was investigated during the years 2000–2005. It was followed by regional and global scale study during the years 2009–2011. It is established that the instability is manifested by occurrence of indicator species and its spatial dominance delineates the areas of potential instability. The investigated inherent characteristic features of the indicator species viz., rapid growth (145cm/year), primary succession, nitrogen fixation and obtrapezoid-winged seed structure, roots and suckers morphology and associated microclimatic scenario have been found extremely decisive to the process of manifestation of slope instability. Study at three experimental sites and vicinity also confirmed that wide-spread occurrence of indicator taxon is not related to specific soil and rock type, gradient or aspect but is exclusively attributable to its unstable environment. The indicator taxon has been identified as Alnus nepalensis D. Don and its invasion delay to the unstable slopes was reported by one to two years. Indicator''s habitat affinity to instability and its phyto-geographical range was explored between 1000–2590m asl at local scale in Garhwal Himalaya and 900–2700m at regional scale in Indian Himalayan and other mountain states viz., Himachal Pradesh, Uttarakhand, Sikkim, Assam and Meghalaya, while it is reported between 200m and 2800m at global scale in Asian countries like Nepal, Tibet, Bhutan, China, Myanmar and Bangladesh. The proposed ecological approach to identify and delineate the areas of potential hill slope instability seems to be promising and may be termed innovative, as it involves only local resource as a scientific tool and traditional wisdom as technical excellence. Unlike geotechnical methods of slope instability assessment, this being simple, eco-friendly, self sustainable and cost effective, it is socially acceptable and can also be used by non-scientists for planning and management in Himalayan region and similar other regions of the world. [Copyright &y& Elsevier]

• Ensemble modeling framework predicting potential distribution of snow trout. • Hydrogeomorphic and climatic variables came out as best predictors. • Mid-elevation rivers were predicted to be highly-suitable for snow trout. • High altitude squeeze: major loss at lagging edge, lesser gain at leading edge. • Cross-boundary climate-adaptive actions required across Himalayan nations. Mountain systems throughout the globe are conspicuously sensitive to on-going climate alterations. This condition is much more detrimental in the Himalaya, where the rate of warming and thus the glacier meltdown is much higher than elsewhere. The Himalayan coldwater species are concerningly most vulnerable to these changes because of their limited thermal range. Whilst climate studies strongly prognosticate the altered distribution of plants and mammals in this region, the impact on coldwater fishes still remains unknown. We used snow trout (Schizothorax richardsonii), a Himalayan coldwater specialist as a model organism to predict the current suitability and climate-driven potential range shift in an ensemble-based modeling framework. We collated occurrence data from a long term, extensive field-based sampling with additional records derived from an in-depth literature survey. A comprehensive input data set including topographic, hydrogeomorphic and climatic variables were used to build correlative species distribution models for the current and future time-periods (2050 and 2070) under three-carbon emission scenarios (Representative Concentration Pathways) by integrating five General Circulation Models. Furthermore, we predicted the elevation-specific range shifts of the snow trout in response to climate change. We predict that a wide-ranging mid-elevation river network is currently suitable for the snow trout in Himalaya, however a significant part of its current distributional range would be lost over time. Our results highlight that snow trout would expand their range upwards into the high-altitude streams with a concurrent predominant range contraction in most of their lagging edges, ultimately creating a high-altitude squeeze. The net habitat loss under three RCP scenarios (RCPs 2.6, 4.5 and 8.5) was estimated to range from 7.41% to 16.29% for the year 2050 which would further increase in the year 2070 ranging from 9.46% to 26.56%. These results provide a strategic information on prioritizing climate-adaptive actions to target the currently suitable habitats and future refugia identified. Our modeling framework also provides a foremost basis to conserve not only the snow trout but also to evaluate the climate impact on several other coldwater species, which are equally vulnerable and ecologically important in the Himalaya. [ABSTRACT FROM AUTHOR]