Poop, DNA help count tigers without sightings, says Tata Institute prof

Nagpur: Tiger droppings, shed hair, and DNA sequencing are quietly transforming how scientists count and monitor India's big cats — often without seeing a single animal — said professor Uma Ramakrishnan, ecologist and molecular biologist at the Tata Institute of Fundamental Research, during her National Science Day address at the CSIR-National Environmental Engineering Research Institute on Thursday.Speaking as chief guest at the event organised by CSIR-NEERI, Ramakrishnan explained how non-invasive genetic tools allow researchers to identify individual tigers, map family relationships, and estimate populations using biological traces left in the wild. By photographing resting sites, collecting hair samples, and sequencing DNA, scientists can track population health while minimising disturbance to animals — an approach especially valuable in dense forests where sightings are rare.
A key breakthrough, she said, was creating a reference genome for Indian tigers. "To understand what genetic variation means, you need a baseline to compare it against," Ramakrishnan noted. Her team built this framework by sequencing the genome of a famous tigress from Ranthambore and assembling a robust reference that researchers can use for years to come. "It may sound unexciting, but without this scale, you simply cannot move forward," she said.Genetic analyses of samples collected across India, Southeast Asia, and the Russian Far East, revealed striking patterns. Indian tigers harbour exceptionally high diversity, Ramakrishnan said. "That places a special responsibility on India because much of the species' future evolutionary potential lies here," she said.The talk also highlighted how genetics help in conservation action. Studies on landscape connectivity in central India were cited in court to argue for wildlife overpasses and underpasses on highways. Conversely, genetic work flagged risks from isolation. Whole-genome sequencing showed tigers in Ranthambore were more inbred than populations elsewhere, underscoring the dangers of small, cut-off reserves.Ramakrishnan explained that Researchers follow mothers and cubs, photograph resting spots, and collect dozens of hairs shed at a single site. Back in the lab, DNA helps reconstruct family trees and even identify fathers—knowledge that was previously impossible without direct observation.The National Science Day event at CSIR-NEERI was attended by scientists, students, and officials, including CSIR-NEERI director Dr S Venkata Mohan.