Uttarakhand builds its first eco-bridge for small animals; What are eco-bridges? Get significance, other details here

The first eco-bridge in Uttarakhand across Kaladhungi—Nainital Highway has been constructed by the Ramnagar Forest Division of the state. The one of its kind bridge has been built to save reptiles and other small animals from vehicular accidents while crossing the road.

According to Amit Kumar Gwaskoti, Kaladhungi Range Forest officer, the 90-feet long and 5-feet wide bridge is the first eco-bridge of the state. He added that it has been constructed in the hope that small animals and reptiles such as squirrels, snakes, monitor lizards will be crossing the road through a bridge and avoid being killed in the accidents.

The Forest officer has also informed that no iron or cement has been used in the construction of the bridge and it is made of eco-friendly items such as rope, bamboo, and grass.

Uttarakhand: An elevated eco-bridge built across a highway in Kala Dungri range of Ramnagar Forest Division to save reptile species from being killed by vehicles

Forest Dept Official says, "This eco-bridge is 90 ft long & 5 ft wide. It's made from bamboo, rope & grass." pic.twitter.com/7yrcKxTqHi

— ANI (@ANI) December 1, 2020

Why eco-bridges are significant for wildlife?

The eco-bridges aims at enhancing the wildlife connectivity that can be disrupted because of the construction of logging or highways.

On the Kaladhungi-Nainital Highway, Ramnagar Divisional Forest Officer, Chandra Shekhar Joshi had supervised the building of a 90-feet long eco-bridge. While talking about the bridge, he informed that many road kills were found on this route, especially of reptiles.

The newly built bridge will be an awareness-building campaign for this very congested tourist route as it will be a way of seeing how the ecosystem necessary for reptiles that feed on insects, the snakes that feed on reptiles, and for the eagles that feed on snakes, can be preserved.

Different form of eco-bridges:

There are various forms of eco-bridges that are beneficial for the conservation of wildlife. These are:

•  Canopy Bridges: These are built usually for squirrels, monkeys, and other arboreal species.

•  Concrete underpasses or viaducts or overpass tunnels: These are built for the conservation of the larger animals.

•  Amphibian tunnels or culverts: It is for the conservation of the smaller mammals.

What builders look at while building the eco-bridges?

The Head of Animal Ecology and Conservation Biology, Wildlife Institute of India, Bilal Habib informs that there are usually two important aspects of building the eco-bridges- location and size.

He explains that when we see roadkill, we think that the animal has died there or we place a bridge there, however, this may not be the only indicator. We don’t often see the collisions because the roads have already become a wall for the animals in that particular area. For example, when highways are upgraded from two lanes to four lanes, we stop seeing the roadkills but it doesn’t mean that it has become a greenway. Therefore, it becomes significant to observe what the animal habitats are in the area, disturbance types, topography, its curvature as well as road length.

Eco-bridge in accordance with animal movement:

The span and distribution of the eco-bridges must depend on the animal movement patterns. The bigger bridges will see nilgai, sambar, wild pigs using them. On the other hand for leopards or tigers, if the bridge is 500 m or 5 m, it will not bother them. But some animals such as barking deer, which prefers close habitats will need smaller bridges.

Success stories and challenges of building eco-bridges in India:

•  Divya Mudappa, Senior Scientist at Nature Conservation Foundation who has been working in Annamalai Hills of Tamil Nadu, built canopy bridges for Nilgiri Langurs and lion-tailed macaques. She informs that 6 bridges were built across a 3-km stretch where the arboreal animals can move freely without being run over. The longest bridge was about 25 m and the smallest was 10 m and these have been very successful with monkeys taking them pretty fast.

•  Bilal Habib informed about his team’s observation on NH-44. It intersects Kanha-Pench and Pench-Navegaon-Nagzira corridors in various sections. There are four minor bridges and five animal underpasses on a 6.6 km road within the forests which makes it one of India’s success stories. The team captured nearly 18 species, including leopard, tigers, and golden jackal, that have been using these underpasses.

Upcoming underpasses for animal conservation in India:

•  For animal conservation in India, one of the largest underpasses of 1.4 km is being built along the Maharashtra-Madhya Pradesh border.

•  Other proposals for underpasses include Chennai-Bangalore National Highway which is in the Hosur-Krishnagiri segment. It is near the reserve forests for elephant crossings.

•  There is also a plan of building an underpass in Tadoba-Andhari Tiger Reserve in Maharashtra.