What Terai tigers eat and what it tells about the habitat

Subject: Environment

Section: Species in news

Context:

The poop of tigers has helped a team of scientists at the Wildlife Institute of India (WII) understand the prey selection patterns of the striped feline in the Indian part of the Terai-Arc Landscape, or TAL.

About the Report:

Report title: The assessment of the food habits of the tiger (Panthera tigris)
Scientists have gather information about the hotspots of conflicts related to livestock predation across 15,000 sq. km of the animal’s habitat along the foothills of the Himalayas.

Terai Arc Landscape (TAL):

TAL is composed of 14 Indian and Nepalese trans-border protected ecosystems of the Terai and nearby foothills of the Himalayas.
The area includes Nepal’s Bagmati River to the east and India’s Yamuna River to the west.
The TAL is home to many endangered mammals including the Bengal tiger (of which it has one of the world’s highest densities), the Indian rhinoceros, the gaur, the wild Asian elephant, the hispid hare, the sloth bear, the South Asian river dolphin and the chital, as well as over 500 species of birds, many endangered.
Examples of birds are the endangered Bengal florican, the sarus crane, and the black stork.
The scientists chose the 900 km linear stretch of TAL, recognised as one of the most productive habitats in the subcontinent.
- The globally important tiger conservation landscape is characterised by a mosaic of forests and grasslands covering both protected areas (PAs) and non-PAs.
TAL represents three major habitat types:
- Shivalik covering parts of the lower Himalayas,
- Bhabar covering the foothills of the lower Himalayas marked by pebbles and boulders, and
- Terai comprises the lowland region below the Himalayan foothills and north of the Indo-Gangetic plains covering entire Uttar Pradesh, southern parts of Uttarakhand, and Bihar.
About 22% of the wild tiger population in India is found across the TAL.

Data-loaded dump:

The dump of an animal yields information about its lineage, genetic relatedness, diet preference, population status, and the use of the landscape.
Field sampling was conducted across:
- six tiger reserves (Rajaji, Corbett, Amangarh, Pilibhit, Dudhwa, and Valmiki),
- two wildlife sanctuaries (Nandhaur and Sohagibarwa),
- two conservation reserves, and
- 11 non-PAs; including nine forest divisions and two social forestry divisions across Bihar, Uttarakhand, and Uttar Pradesh.
What does the data reveal about dietary patterns?
- Large-bodied species – sambar, swamp deer, nilgai, chital, wild pig, and livestock – comprised about 94% of the diet, with sambar, chital, and livestock having the highest relative proportions.
- Habitat-specific (Shivalik-Bhabar and Terai) analyses indicate that prey selection is driven by prey abundance and body weight but not determined by protection status (PAs versus non-PAs).
- PAs and non-PAs in the Terai region were more prone to livestock predation-related conflict.
Large carnivores have significant role in maintaining ecological diversity and interactions within their respective biological communities.

Recommendations:

Prey abundance estimation outside the PAs,
Reduction of grazing pressures, and
Detailed records of tiger mortalities with causal investigations to ensure future conflict-free tiger persistence across the TAL.