Nationwide bat assessment after 2 decades finds 135 species, 16 endemic to India

The study found West Bengal (68 species), Meghalaya (66 species), and Uttarakhand (52 species) are India’s bat diversity hotspots

India is home to 135 bat species, including 16 endemic, but they are among some of the least studied mammals, with 35 species still data deficient or unassessed, even as habitat loss, tourism pressure, and urban expansion reshape their roosts across caves, monuments, and cities, a study has found.

The previous national assessment was carried out nearly two decades ago.

Thirty-four experts from 27 institutions carried out the two-year study titled ‘State of India’s Bats’. The Nature Conservation Foundation (NCF) and Bat Conservation International (BCI) released it on Tuesday in collaboration with the World Wildlife Fund (WWF) India.

The study found West Bengal (68 species), Meghalaya (66 species), and Uttarakhand (52 species) are India’s bat diversity hotspots. Punjab and Haryana had the least diversity among states, reporting just five species each. Delhi has 15 bat species. The previous national assessment, carried out nearly two decades ago, found 120 bat species.

The report said only seven species are classified as threatened, but warned this is likely an undercount, due to data gaps in covering bats across the country. “Despite their crucial roles in the ecosystem as seed dispersers, pollinators, and predators of pest insects, bats receive an insignificant amount of attention from the country’s research and conservation communities and scant recognition in government policies and programmes,” the study said.

Out of the 16 species endemic to India, four were found endemic to the Himalayas and northeast India

The study noted that there are fewer than 50 dedicated bat researchers throughout India, each trying to study and conserve these “misunderstood animals” with limited resources and support when compared to those available.

Out of the 16 species endemic to India, four (the Sombre Bat, the Meghalaya Thick-thumbed Bat, the Rainforest Tube-nosed Bat, and Peter’s Tube-nosed Bat) were found endemic to the Himalayas and the northeast. Four species endemic to the Western Ghats included Salim Ali’s Fruit Bat (Latidens salimalii), the Pomona Leaf-nosed Bat (Hipposideros pomona), Peyton’s Whiskered Myotis (Myotis peytoni), and Srini’s Long-fingered Bat.

Experts said data gaps and a lack of knowledge around bats, particularly government data, remain a challenge. “We have extremely limited government data. When a sighting is made, or we need information, most bat researchers reach out among themselves,” said Zoo Outreach Organisation (Hyderabad) research affiliate Aditya Srinivasulu, who was part of the study.

Thangsuanlian Naulak, a PHD student and bat researcher, said the stigma attached to bats is linked to the lack of research on the species, even as bats are key pollinators, seed dispersers, and natural pest controllers, and play an important role in the ecosystem. “They are considered akin to pests or rats in the skies. After Covid 19, this stigma has only increased,” said Naulak.

The report said India hosts several data deficient bat species (like the Peters’s Tube-nosed Bat and Wroughton’s Free-tailed Bat). It added there is inadequate information on their taxonomy, distribution, population size, and/or ecology. “These species are often neglected in conservation planning due to the lack of baseline data, and addressing this requires targeted surveys and research to fill knowledge gaps.”

Where bats live was flagged as a key structural vulnerability. Most species were found roosting outside protected forests, in caves, temples, forts, tree hollows, and urban structures, from old buildings to drainpipes.

The report said India’s largest bat colonies are often found in human-made structures, especially historical monuments. It flagged repeated conflicts between bat conservation and monument management. The report noted that the Archaeological Survey of India (ASI) has removed bats over the years by installing bright lights and carrying out chemical cleaning.

The ASI is responsible for managing historical monuments, which have often been critical of bats on-site. “At sites like Qutb Minar, Khirki Mosque, Feroz Shah Kotla, and Agrasen ki Baoli in Delhi and Daulatabad Fort in Maharashtra, restoration efforts have included installing bright lights and sealing off roosting spaces, which disrupted resident bat colonies,” the study said.

It added that chemical cleaning was, in some instances, used to remove bat guano, deterring roosting. The report said that in only rare cases, bats have been allowed to roost, for instance at the Golconda Fort in Hyderabad, or Delhi’s Zafar Mahal in unused chambers.

NCF and BCI’s India Bat Project manager Rohit Chakravarty called for the need for co-existence. “The report highlights how there are limited roosting spaces for bats, including monuments, but in a lot of cases, they are being removed from these spaces. The study wants to highlight how 35 species are data deficient, which essentially means there is limited data around them. A number of these are endangered and hard to find, and thus, require attention,” Chakravarty said.

“Unlike the India State of Birds report, which has bright photos and data on which species of birds are increasing or decreasing, we have no such comparison for bats, because we have so little data on these species.”

The report called for scaling up surveys, improving taxonomic clarity, and integrating bats into environmental policy, impact assessments, and tourism planning.