Trace DNA left by large carnivores at livestock kill sites can be used to reliably identify individual predators: NCBS study
NCBS said that this approach offers a powerful tool to effectively manage human-wildlife conflict and understand predator behaviour and ecology.
'In communities that live in proximity to large carnivores, livestock depredation might cause conservation challenges. Systematic understanding of individuals involved in conflict is a critical first step towards a solution,' said Uma Ramakrishnan, senior author of the study which has been published in Biological Conservation.
NCBS said that around the world, managing human-wildlife conflict often involves relocating or removing the suspected predator.
'Typically, forest departments rely on field signs like pugmarks, scat, or claw marks to identify the animal involved. However, these signs can be ambiguous, and removing the non-target individual may disturb carnivore populations and sometimes further intensify conflict situations. More reliable and robust genetic identification of predators could be an effective strategy for conflict resolution,' NCBS said.
The researchers in collaboration with Panthera and the Madhya Pradesh Forest Department investigated 198 kill sites across two of Central India's key tiger habitats - Kanha and Bandhavgarh Tiger Reserves.
At each site, researchers collected non-invasive genetic samples - saliva, scat, and shed hair as a potential source of predator DNA.
Using genetic tools based on Single Nucleotide Polymorphisms (SNPs), they identified individual tigers present at these kill sites. Shed hair samples were the most effective for individual identification, followed closely by saliva and scat.
Overall, tigers were successfully identified at 85% of the kill sites, with species-level identification exceeding 95% across all sample types.
To assess each tiger's likely involvement in a kill, the team developed a classification framework based on the type and location of genetic evidence. Each case was categorised as a true predator (high confidence),circumstantial predator (medium confidence), or predator uncertain (low confidence).
Out of the 198 cases studied, 72 were classified with high confidence, 34 with medium confidence, and 49 with low confidence.
'Genetic samples are often the only true evidence of a predation event and are therefore vital. While identification is possible, there remains some possibility of misidentification especially when multiple individuals are present at the kill site. That's why it's important to assign confidence levels in identification. We hope that such a classification scheme will help better represent the level of confidence provided by the genetic tools and further evidence-based conflict management,' said Himanshu Chhattani, lead author of the study.
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