The latest report by researchers assessing the physiological stress response of wild Asiatic elephants in the Western Ghats shows that elephants can adapt to human presence, but are adversely affected by aggression from the human trying to drive them away from their plantations. With elephants venturing out into or passing through human settlements frequently, this study looks at stress levels among wild Asian elephants, to understand how the gentle giants respond to being driven away aggressively by humans. The team of researchers, led by Sreedhar Vijayakrishnan, Ph.D. scholar at National Institute of Advanced Studies, Bengaluru, studied and measured the levels of glucocorticoids, a class of steroid hormones found in the faeces of elephants when they are stressed. This non-invasive measure of study of “faecal glucocorticoid metabolite concentrations are a fairly reliable indicator of stress and is used across species,” explained Vijayakrishnan. The study conducted in two different types of neighbouring habitats studied faecal droppings of elephant herds in a relatively undisturbed surrounding of the Vazhachal Reserve Forests, and the Valparai Plateau with its myriad tea, coffee and cardamom plantations, thus within easy range of human-dominated habitation. While traversing the plantations in the Valparai Plateau, the elephants are sometimes driven away by resident humans using loud vehicles, sirens and fire-crackers. The researchers collected and studied the faecal droppings in the Valparai Plateau before and after these drives, and compared them to those in the Vazhachal Reserve Forests. The study found that the stress levels of elephants in the plantation dominated human settlements of Valparai was not much different from those in the undisturbed forests of Vazhachal, proving that elephants coming in direct contact with humans adapt themselves to human habitation, and exist without stress. The stress levels, worryingly, shoots up after the aggressive drives, with glucocorticoid concentrations rising by more than 100 percent in calves, and 55 percent in sub-adults, with a 24 percent increase seen in adults, by which can be deduced that adults are more experienced in handling stressful situations than juveniles. Vijayakrishnan urges for such aggressive and prolonged drives to be avoided, while he lays stress on the fact that “any invasive management action such as drives, translocation, and capture should take into consideration the behavior and physiology of the animal involved.”
— As reported by Mongabay
Cover Photo: Elephant feeding on Ochlandra (Indian bamboo) inside a wet evergreen patch in the Anamalai hills, southern India. Photo by Sreedhar Vijayakrishnan, Courtesy: Mongabay India