Altitudinal gradients and species richness: A study on diversity of orthoptera in Nilgiris Shola Forests and Grasslands

Uplands provide refuge for insects subject to lowland habitat loss, but information on their response to climate change is lacking particularly orthopterans. There is a significant reduction in the diversity of grasshoppers however a shift of highly mobile and polyphagous insects towards higher altitudes is prevalent, in the era of climate change. Our study on the diversity of grasshoppers in the Nilgiris shola forest supported that the shift of grasshopper from mid-altitude to high altitude. The high values of Shannon’s diversity index (H’) were recorded in Nedugula (1.43) followed by Longwood (1.34) and Avalanche shola forests (1.29). The species distributed only in lowland forests are now recorded in the high altitudinal stunted wet evergreen shola forests. It is evident from our study that the upland forests provide refuges to highly mobile insects like grasshoppers when lowland sites have an impact on climatic fluctuations.