In a tragic incident that has alarmed conservationists, an endangered hoolock gibbon was electrocuted on a railway line passing through one of Assam’s most biologically rich forests, once again highlighting the serious risks the track poses to wildlife.
Although the railway line has long been considered a threat to animals in the area — particularly tree-dwelling species like hoolock gibbons — recent electrification of the track without adequate mitigation measures has significantly increased the danger.
Forest officials confirmed that the victim was an adult male gibbon found dead due to electrocution inside the Hollongapar Gibbon Wildlife Sanctuary near Mariani in Jorhat district.
Arboreal animals such as gibbons rarely descend to the ground, as they avoid open spaces where they become vulnerable to predators and vehicle movement. However, the railway line has fragmented the forest canopy, forcing animals to take risky routes. Gibbon families living on either side of the track — especially the four to five groups in the smaller Compartment I — are now effectively cut off from each other.
The hoolock gibbon, India’s only ape species, enjoys the highest level of legal protection under Schedule I of the Wildlife (Protection) Act, 1972. Despite repeated appeals from experts to reroute the 1.65-km railway stretch outside the sanctuary, authorities proceeded with electrification, raising concerns over the species’ long-term survival.
Conservation organisations, including the Wildlife Institute of India (WII), have recommended installing artificial canopy bridges at key points to allow arboreal animals to cross safely. However, many experts argue that relocating the short railway stretch outside the sanctuary would be the most effective permanent solution.
Primatologist Dr. Dilip Chetry noted that the railway line has turned the sanctuary into a “forest island,” cutting it off from surrounding habitats. He warned that gibbons, which depend entirely on continuous forest canopy, are among the worst affected. The fragmentation has also reduced genetic exchange between groups, further threatening their survival.
Earlier attempts to install artificial canopy bridges were unsuccessful, as the designs did not match the specialised brachiation movement of gibbons. WII had suggested building seven properly designed canopy bridges, but experts caution that any future doubling of the railway line could make such mitigation measures ineffective.
Spread over just 20.98 square kilometres, Hollongapar Gibbon Wildlife Sanctuary is home to seven species of primates — the highest diversity in Assam — including around 125 hoolock gibbons living in 26 groups.
