NHAI, in collaboration with the wildlife institute of India(WII), has released the landmark report ‘landscapes reconnected’ presenting the first scientific evidence of wildlife successfully using animal underpasses on the Delhi-Dehradun Economic Corridor….PIB
Dehradun: One of Asia’s longest elevated wildlife corridor, a 12-km stretch of the Delhi-Dehradun Expressway arching over the Mohand area, is showing early signs of successful animal movement, with a joint study by the Wildlife Institute of India (WII) and the National Highways Authority of India (NHAI) documenting a range of species moving beneath the structure.
The 213-km expressway, connecting Akshardham in Delhi to Dehradun, is set to be inaugurated by PM Narendra Modi on April 14.According to the study, ‘Landscape Reconnected: First Evidence of Wildlife Movement across the World’s Largest Animal Viaduct on NH-72 (Asharodi–Ganeshpur)’, at least 18 species, including carnivores, herbivores, ungulates, pheasants and primates, have been recorded using the underpasses along an 18-km stretch between Ganeshpur in UP and Asharodi on the outskirts of Dehradun.
Among the animals documented were elephants, leopards, spotted deer, sambar, nilgai, golden jackals, peacocks and wild boar, indicating active and diverse use of the passages.Golden jackals were the most frequently recorded species, followed by nilgai, sambar and spotted deer. Smaller mammals, including the Indian hare, also showed consistent movement through the structures. Notably, elephants were recorded using the corridor on at least 60 occasions, indicating that even large mammals are navigating the infrastructure while maintaining natural movement patterns, the study stated.
The findings are based on a 40-day monitoring exercise that analysed over 1.1 lakh images captured through systematically deployed camera traps and 29 AudioMoth acoustic recorders along the corridor. Officials said the monitoring setup was designed to detect a broad spectrum of terrestrial fauna, ranging from small to large-bodied species.The 20-km stretch between Ganeshpur and Asharodi features nearly 11 km of dedicated animal underpasses designed to facilitate unobstructed movement.
The elevated corridor, with an average height of six to seven metres, is among the “largest of its kind in Asia” and is built to accommodate even large mammals such as elephants.“This is the world’s largest viaduct of 12 km. It will help in the unobstructed movement of wildlife from Uttarakhand to Himachal Pradesh and Haryana,” said Bilal Habib, scientist at WII, and lead author of the study.According to the report, the landscape falls within the Terai Arc, one of the country’s most critical conservation zones, forming the westernmost distribution range of species such as tigers, elephants, greater hornbills and king cobras.
It added that the expressway passes through the Shivalik Elephant Corridor, spanning the Shivalik forest division, the westernmost edge of Rajaji Tiger Reserve and the Dehradun forest division.The study also identified soundscape management as a key factor influencing wildlife movement. While generalist species such as jackals and wild boar appeared tolerant of traffic noise, more sensitive species like elephants and deer preferred quieter underpass segments.
Researchers suggested targeted noise barriers in high-use areas to improve effectiveness.Offering a more cautious view, former dean of WII, YV Jhala, said that while such corridors are a positive step, movement alone does not guarantee settlement. “If there is a source population of tigers in western Rajaji, they may move towards the Shivalik forests. But the Shivalik forests in UP have a poor prey base, which limits further movement towards areas like Kalesar in Haryana or Himachal.
Wildlife needs not just passage, but viable habitat,” he said, adding that until prey populations recovered, large carnivores are unlikely to establish themselves beyond certain zones.Earlier, TOI had reported in 2021 that nearly 55% of the last 20-km stretch of the expressway falls within critical wildlife crossing zones, citing a WII study on mitigation measures in the Shivalik hills.Local environmentalists also urged caution in interpreting early findings. “The study was conducted before the expressway became operational. It is yet to witness full traffic volumes, especially during peak tourism seasons. A more accurate assessment will only be possible once the road is fully in use,” said Dehradun-based environmentalist Reenu Paul.
