Habitat fragmentation threatens endangered Hoolock gibbons in Northeast India

Populations of the western and eastern Hoolock gibbon, India’s only ape, have declined by 90% over recent decades due to severe forest fragmentation by linear infrastructure.

Railway expansions begun in Eastern Assam in 1887 isolated populations like the Hoollangapar Gibbon Sanctuary, which now houses approximately 130 western Hoolock gibbons.

Conservationists have successfully implemented natural canopy bridges through dense tree planting alongside railway tracks to reconnect fragmented arboreal habitats.