Research Highlight

Forests in India’s Tiger Reserves browning, drying up

doi:10.1038/nindia.2019.143 Published online 29 October 2019

A view of the Ranthambore National Park in Rajasthan, India.

.© S. Priyadarshini

Analysing long-term satellite data, wildlife biologists have revealed that about half of India’s Tiger Reserves (TRs) are facing vegetation browning and drying.

TRs receive the highest legal protection among India’s protected forest areas, and the researchers say the conditions of vegetation in some TRs are similar or even worse than the less-protected Wildlife Sanctuaries (WLSs).   

Since the inception of India’s Project Tiger in 1973, there has been no scientific data on the effectiveness of TRs in conserving the tiger and its habitat.

To assess the TRs’ roles in forest conservation, scientists from the Centre for Wildlife Studies in Bangalore, India, and the US-based Google Inc and Duke University studied almost three decades of satellite data on Indian land. They matched TRs’ roles in forest conservation with those of WLSs by analysing greenness, moisture, brownness and the drying of vegetation. 

Of the TRs, five showed better vegetation conditions and five showed worse vegetation conditions than their matched WLSs. The comparison was ambiguous in Sundarban TR in West Bengal, whose area under both improvement and decline were simultaneously greater than in its matched Chintamani Kar WLS.

In the years after the declaration of TRs, vegetation conditions have improved over more than 50 per cent of their areas in two of the 25 TRs: Satpura TR in Madhya Pradesh and Bandipur TR in Karnataka, with Bandipur TR showing improvement over 90 per cent of its area.

Vegetation condition also deteriorated over more than 50 per cent of their areas in 13 out of 25 TRs. This, the researchers say, challenges the effectiveness of greater protection and management resources alone in safeguarding the long-term viability of habitats of the tiger as a threatened species. 


1. Koulgi, P. S. et al. Extensive vegetation browning and drying in forests of India’s Tiger Reserves. Sci. Rep. 9, 14976 (2019)