Hanuman langurs abandoning leaves for processed bread, peanuts, finds DST study
The study also pointed out that langurs are very thoughtful about their food selection, which is independent of human interferences and scarcity of natural food items, according to a note on the department’s website
A new study funded by the Department of Science and Technology on hanuman langurs (semnopithecus entellus) used widely to scare off monkeys in cities found that they have started developing a taste for urban food, particularly bread and processed peanuts. Their primary natural diet is leaves.
The yet-to-be-published paper traces the urban adaptation of langurs coexisting with humans.
The study also pointed out that langurs are very thoughtful about their food selection, which is independent of human interferences and scarcity of natural food items, according to a note on the department’s website.
Union science minister Harsh Vardhan also tweeted the findings of the study.
The species is folivorous (herbivore that eats leaves) but they have developed a taste for processed foods.
The study could provide important insights into the adaptation of non-human primates for their conservation, better management, and policy-making to develop a sustainable urban ecosystem, the department said.
Manabi Paul from the Department of Environmental Science, University of Calcutta, headed the study on behavioral adaptations of urbanized non-human primates whose habitat ranges overlap with human settlements. “The findings have not been published in a journal yet. We will share the paper as soon as it is out,” she said.
Her team conducted 83 field-based experiments across West Bengal between December 2018 and March 2020 to understand the feeding pattern of these folivorous colobines (a subfamily of the old-world monkey family) who have a multipartite stomach that facilitates the fermentation of leafy diet.
The experiments have been interpreted by mathematical modeling to understand the feeding preferences of these free-ranging non-human primates within an urban ecosystem.
“They are extremely adaptable creatures. Yes, their natural diet is leaves but they have adapted very well to co-exist with humans. Similarly with rhesus macaques, who are frugivorous but now eat urban human food. This only shows how adaptable langurs are. Eating such foods are not good for them in the long run because they develop various diseases and tend to become obese. In many places humans feed them urban foods,” said Sindhu Radhakrishna, professor, National Institute of Advanced Studies, Bengaluru.