While the impacts of road networks on the safety and movement of large mammals such as elephants and tigers are widely reported, such infrastructure could have much more serious consequences for smaller animals and reptiles such as the little-known Xylophis perroteti, commonly known as the Perrotet’s mountain snake and the Striped narrow-headed snake.
Recent research suggests that the reptiles, which are endemic to the Western Ghats and restricted largely to the Nilgiris hills, use the roads for thermoregulation, putting them directly at risk from being run over by vehicles.
One among the five recognised species of the Xylophis genus, all endemic to the Western Ghats, scientists note that very little is known about the population trends of all five species, including the Perrotet’s mountain snake.
P. Santhoskumar, a biologist from the Mudumalai Tiger Reserve who has studied the species, its population, diet, habitat, breeding habits and also the threats it faces, has recorded 134 road kills of the species, over a course of 72 days along 1,440 km of total roads surveyed. This was published in a 2017 paper in the Russian Journal of Herpetology (Impacts of Roads on the Mortality of Endemic Striped Narrow Headed Snake).
The researchers noted that the most number of road kills of the species were recorded during the monsoon, followed by the pre-monsoon and finally the post-monsoon season. Usually found only in the higher elevations of the Nilgiris, the species becomes more active during the breeding season, which is during the monsoon, Mr. Santhoshkumar, told The Hindu.
“Our research has also shown the majority of the road kills actually occurred close to plantations, followed by Shola forests, agricultural areas and a few near human habitations,” he said. Such a huge number of individual deaths due to road kills could negatively affect the chances of continued survival for the species, he noted.
While the long-term prospects for the species in the Nilgiris could potentially be threatened by other factors such as climate change, the more immediate threats highly endemic species like the Perrotet’s mountain snake as well as amphibians are from roads, and the ensuing vehicular traffic through wooded and green areas, said Mr. Santhoshkumar.
