Predicting the distributions of predator (snow leopard) and prey (blue sheep) under climate change in the Himalaya

Future climate change is likely to affect distributions of species, disrupt biotic interactions, and cause spatial incongruity of predator–prey habitats. Understanding the impacts of future climate change on species distribution will help in the formulation of conservation policies to reduce the risks of future biodiversity losses. Using a species distribution modeling approach by MaxEnt, we modeled current and future distributions of snow leopard (Panthera uncia) and its common prey, blue sheep (Pseudois nayaur), and observed the changes in niche overlap in the Nepal Himalaya. Annual mean temperature is the major climatic factor responsible for the snow leopard and blue sheep distributions in the energy‐deficient environments of high altitudes. Currently, about 15.32% and 15.93% area of the Nepal Himalaya are suitable for snow leopard and blue sheep habitats, respectively. The bioclimatic models show that the current suitable habitats of both snow leopard and blue sheep will be reduced under future climate change. The predicted suitable habitat of the snow leopard is decreased when blue sheep habitats is incorporated in the model. Our climate‐only model shows that only 11.64% (17,190 km²) area of Nepal is suitable for the snow leopard under current climate and the suitable habitat reduces to 5,435 km² (reduced by 24.02%) after incorporating the predicted distribution of blue sheep. The predicted distribution of snow leopard reduces by 14.57% in 2030 and by 21.57% in 2050 when the predicted distribution of blue sheep is included as compared to 1.98% reduction in 2030 and 3.80% reduction in 2050 based on the climate‐only model. It is predicted that future climate may alter the predator–prey spatial interaction inducing a lower degree of overlap and a higher degree of mismatch between snow leopard and blue sheep niches. This suggests increased energetic costs of finding preferred prey for snow leopards – a species already facing energetic constraints due to the limited dietary resources in its alpine habitat. Our findings provide valuable information for extension of protected areas in future.     

Structure and photophysics of a Schiff base-bipyridine ligand and its rhenium(I) tricarbonylchloro complex

A new Schiff base-bipyridine ligand, [4-(4′-methyl)-2,2′-bipyridyl)imine]-2-hydroxybenzene, was prepared, characterized and its X-ray crystal structure obtained. The rhenium(I) tricarbonylchloro complex of this novel derivative of 2,2′-bipyridine was also prepared and characterized. The photophysics of both of these compounds were explored. The absorption spectrum of the Schiff base in acetonitrile possessed bipyridine based π → π^∗ transitions at 246 and 278 nm along with a phenolic charge transfer absorption at 360 nm. Acetonitrile solutions of this compound were found to be luminescent at room temperature with an emission maximum at 435 nm. The rhenium(I) metal complex prepared from the Schiff base exhibited wavelength dependent metal-centered and ligand-centered emission at wavelengths shorter than the analogous rhenium(I) compound prepared from 4′-formyl-4-methyl-2,2′-bipyridine.