Alumna Update: Udita Bansal
Udita Bansal is a 2017 scholar. She has a M.Sc in Ecology, Evolution and Conservation from Imperial College.
In this week’s post Udita shares with us the alarmingly high rate of animal mortality due to vehicular collision, reptiles in particular, and the mitigation measures we can put into place to reduce it.
Hit & Run! Reptile roadkills in Western Ghats and mitigation measures
Animal Mortality Rates by Species
Can you imagine living in a world without roads? A world where we would be walking through thick forests or deserts, or hiking up and down mountains to arrive at our destination. Probably without realising it, we consider roads to be a part of the positive spaces in which with live. However, have you ever stopped to wonder what we lose when we pave new roads?
While roads connect various types of human settlements, they also form “linear infrastructure intrusions” through natural habitats such as forests, oceans and grasslands. Roads cut through forests forming fragmented patches of what was originally a single ecosystem. This is very disorienting for animals as roads often become barriers to movement of animals across the landscape. Herds, flocks are often separated by these divisions. For animals with home ranges larger than the given patch, this causes immense stress. They are forced to find all their resources, including food, shelter and mates, within the smaller area they’re left with, thereby exhausting resources, causing inbreeding and the faster spread of diseases etc. This fate has befallen several animal species which are rare and endemic to certain areas, such as the orangutans which are only found in Borneo and Sumatra. As humans rapidly “develop the land” we run the risk of further boxing orangutans into smaller habitats, ensuring their extinction.
Illustration of the process of transformation of natural landscapes due to development of roads
Highways that run through forests or other terrestrial landscapes are known to be a major cause of animal mortality worldwide. Vehicular collisions with crossing animals are extremely commonplace on highways surrounded by natural landscapes or on smooth roads where traffic drives at extremely high speeds. The number of dead animals found on the highways is staggering.
I studied reptile roadkill on an inter inter-state highway connecting Karnataka and Kerala that passes through the Brahmgiri Wildlife Sanctuary in the Western Ghats. I have an affinity for reptiles, snakes in particular. When a friend alerted me of the astounding number of snakes that they saw on the road I knew I had to study this myself and find a solution to the problem. Reptiles are most prone to being hit and run victims of all the animal groupings, including amphibians, reptiles, insects and mammals. During the span of a week I found over 60 dead reptiles on an 18 km stretch of road with the mortality rate of snakes being higher than that of lizards. Given their size, drivers aren’t able to spot snakes until it is too late and to make matters worse, snakes are a taboo in India, therefore drivers are known to go out of their way to run them over. What I find particularly heart-breaking in my research is to find carcasses of snake species that I have yet to encounter in the wild.
Roadkill- Coral Snake
I’m sure you’re wondering, what lures reptiles to the road more than any other species? Like most other species reptiles cross roads to go from one patch of habitat to the other but roads – tar roads in particular – are also the perfect spot for these cold blooded critters to bask in the sun. Roads have the ability to heat up quickly and retain it long after the sun has gone, they also provide unobstructed access to the sun. This is why it’s unsurprising to find these snakes coiled in the middle of the road. I once found a coiled coral snake dead in the middle of the road. These beautiful black and red coloured snakes are rare to find in the wild.
Illustration of Culvert with Fences
Using the data I have collected, I have located hotspots of snake-vehicular collisions along the 18km stretch of highway through the Brahmgiri Wildlife Sanctuary. Armed with this information we are better able to create solutions that can lessen the chances of animal fatalities. Some of the simplest solutions that can be put into effect immediately are – introducing speed limits and speed breakers which ensure that cars slow down enough to allow animals to escape to safety; regulating the number of vehicles allowed on the highway each day; temporarily closing roads at night or during breeding season when animal activity maybe higher. Other mitigation measures could include the construction of underpasses or culverts under highways as safer crossing options for animals; metal boards can also be placed on the side of the roads as sun basking spots for reptiles.
Most of these measures do not require much effort or monetary funds, and can be introduced before, during or after road construction. The more we study wildlife habits, the better informed our mitigation measures will be. It is important that planning committees and citizens alike be conscious of the consequences of development and actively participate in the conservation efforts. It is keeping this in mind that conservation organisations have created phone applications that encourage community participation. One such application is Roadkills created by the Wildlife Conservation Trust. Roadkills is a citizen science project that engages concerned citizens in collecting data on mortality of wild animals on roads, railway lines and irrigation canals across the country. The data is collected in the form of geotagged photographs which users of the app click when they come across a roadkill.
As I conclude this article I would like to leave you with a few parting requests and thoughts. I hope the next time you are driving down a highway you will not overspeed, keep an eye out for wild animals when crossing green areas and record any roadkill you encounter on the Roadkills app so that scientists and wildlife conservationists can use that data and save some animals, if not all, from extinction. By doing so you might even sight some animals that you may never see on expensive wildlife safaris. I once saw an Aardwolf while driving in South Africa and it is one of my most cherished sightings till today.
Artwork by Ragini Chawla
