Trains inadvertently helping snakes expand habitat in Goa: Study

Snakes, including king cobras, may be inadvertently expanding their habitats in Goa, with trains acting not only as corridors for active movement, but also as high-speed conduits, according to a study.

Media reports in recent times have highlighted incidents of snakes in India's trains. Volunteers from animal rescue organisations are often called in to remove the reptiles.

Researchers, led by herpetologist Dikansh Parmar from Germany's Leibniz Institute for the Analysis of Biodiversity Change, said the conservation status of king cobra population in and around the Western Ghats, or 'Ophiophagus kaalinga', requires attention.

The study, published in the journal Biotropica, is the "first detailed documentation on the distribution and natural history of the Western Ghats King Cobra, Ophiophagus kaalinga, in Goa, and its interesting apparent interaction with railway infrastructure, which may influence its distribution".

The team combined rescue records, verified sightings and local reports with historical data and documented 47 localities where O. kaalinga has been found in the state across a period of 22 years (2002-2024) — 42 records of locations from suitable habitats throughout Goa were used to build a distribution model.

Locations from five rescue records of the king cobra species were found to fall along busy railway corridors, an unsuitable habitat, for which the researchers' model predicted the lowest odds — such as a railway station in Chandor Village, South Goa.

Rescue events were also used as an opportunity for informally interviewing local residents about the general presence of king cobras in villages and surrounding areas.

"Combined with recent reports of snakes on trains in India and of O. kaalinga in a rail yard, entirely unsuitable reptile habitats, we propose the hypothesis that snakes, king cobras included, may inadvertently expand their ranges by accidental transport on trains," the authors wrote.

They said the hypothesis opens up a new, fascinating line of ecological research into how linear infrastructure such as railways may act as a barrier, but also, inadvertently as a conduit for wildlife movement.

Looking at the study's findings and existing knowledge together and involving snake rescue NGOs and a citizen science network of local residents may help better understand the environmental challenges that the "iconic" snake faces, they said.

Further, the study shows how snake-rescue NGOs not only help with saving snakes, but also in long-term species monitoring. A collaboration between rescuers and researchers, as demonstrated in the study, illustrates how rescue data can inform research on vulnerable taxa and help with evidence-based species management decisions, the authors said.