Impact of Climate Change on the Distribution of Endemic orchid Habenaria grandifloriformis Blatt. & McCann in Peninsular India

The present study investigated the species distributional model of Habenaria grandifloriformis Blatt & McCann in Peninsular India using the MaxEnt model under two climate change scenarios (SSP2-4.5 & SSP5-8.5). Both primary (field surveys) and secondary data (herbarium & literature surveys), along with aspect, elevation, slope, and 19 bioclimatic variables, were used to determine the current and future habitat suitability of the species. A total of 249 occurrence records were taken into account, out of which 30% were used as training data. Of the total study area, 51332.33 km2 (2.93%) is highly suitable for the species. The model projects a substantial decrease in the future by 4.93% to 25.90% under SSP2-4.5 and 4.10% to 49.13% in SSP5-8.5 scenarios by 2090. A state-wise analysis indicates that Maharashtra has the highest suitable habitat and is projected to decrease in the future, except in 2040. The present study highlights that the Maximum Temperature of the Warmest Month (Bio5) and Annual precipitation (Bio12) were the most significant variables in the model, followed by Precipitation Seasonality (Bio15), which also contributed substantially to the species distribution. Moreover, Rajasthan is projected to have more than 100 km2 of suitable habitat under future climatic conditions in both scenarios. As the habitat of the species is severely threatened by tourism and other human activities, this study provides baseline data on probable suitable habitat to support conservationists in taking essential steps for the species' protection.