Kolar Bats are nature’s pest controllers, finds OU study

Researchers from Osmania University have used faecal DNA metabarcoding to study the diet of bats, identifying their role in controlling insect populations that affect agriculture and public health.

The study analysed faecal pellets collected from four species of leaf-nosed bats — Kolar Roundleaf Bat (Hipposideros hypophyllus), Hipposideros durgadasi, Hipposideros fulvus and Hipposideros speoris — sharing a cave at Hanumanahalli in Kolar district, Karnataka.

According to researchers Chelmala Srinivasulu, head, Wildlife Biology and Taxonomy Lab at Osmania University; lead and co-author Srinivasulu, B. and A. Srinivasulu, the samples were collected from bats returning to the roost after their first feeding bout across three seasons between 2021 and 2022. DNA analysis identified 7,309 Operational Taxonomic Units belonging to the phylum Arthropoda.

The cave is the only known habitat of the Kolar Roundleaf Bat, with a population fewer than 300. They found that the species consumed 4,114 insect taxa, while the other three species fed on between 1,200 and 2,400 taxa. The study identified a core diet of 48 taxa from 10 insect orders, 37 families and 46 genera.

While the overall diets were similar, differences in core diets indicated that each bat species specialised in different prey. Seasonal changes were also recorded, with moths forming more than 70% of the Kolar Roundleaf Bat’s diet during the monsoon and winter.

The bats consumed mosquitoes linked to dengue and malaria, agricultural pests including the tomato leaf miner moth, and other insect pests, indicating their role in biological pest control.

The research was funded by Bat Conservation International, Texas, through its Endangered Species Grant. Additional support was provided by the Department of Science and Technology-Science and Engineering Research Board (DST-SERB), and the University of Reading through an International PhD Studentship. The findings have been published in the Journal of Threatened Taxa.