- A new study finds that habitat loss and fragmentation in central India are putting key wildlife corridors at risk and disrupting tiger dispersal.
- Using satellite imagery the researchers tracked landscape shifts over time, mapping forests, agricultural land, scrub, water bodies, and settlements and found that more than 40% of the landscape is poorly suited for tigers.
- Protecting key corridors, limiting new development, restoring degraded forest patches, and strengthening buffer zones could improve connectivity in tiger habitats, the study notes.
Across the forests of central India, young tigers set out on long journeys once they reach two to three years of age; they leave their mother’s territory and search for their own. But the surrounding landscapes are no longer as conducive. Once continuous forest blocks are now fragmented by farms, roads, rail lines, and settlements.
A recent study published in the Journal for Nature Conservation examines how tigers navigate such altered terrain. The study was conducted by researchers from the Indian Institute of Remote Sensing and the Institute of Integrated Learning in Management (IILM) University. “Many studies talk about habitat loss. Our focus is on building computational models that use data to understand [habitat] connectivity,” says Saurabh Shanu, Assistant Dean and an associate professor at IILM University, and one of the study’s co-authors. The goal was to identify which parts of the landscape still allow safe passage for tigers, and which are at risk of being lost.
To achieve this, the researchers combined satellite data with two analytical approaches — graph theory and game theory. “Graph theory helps us connect different places on the map. Game theory helps us understand how a tiger responds to things like prey, roads, or other animals,” Shanu explains. Together, these tools map not just where forests remain, but how usable they are for wildlife.
A changing landscape
Central India holds about 40% of the country’s wild tigers, with recent estimates placing the population at around 3,682 individuals. Yet the landscape they depend on is changing.
Between 2005 and 2015, forest cover in the study area shrunk by about 5%, while agriculture and settlements expanded. By 2015, non-forest land accounted for more than half the region.
The study focused on six tiger reserves: Panna, Pench, Bandhavgarh, Sanjay-Dhubri, Achanakmar, and Indravati. These reserves are linked by corridors — stretches of land that allow animals to move between habitats — which are vital as they provide young tigers space to disperse and maintain healthy populations.
Using satellite imagery and GIS data, the researchers tracked landscape shifts over time, mapping forests, agricultural land, scrub, water bodies, and settlements.
This builds on an earlier network analysis by Shanu and collaborators, which mapped the key forest patches linking reserves. “Before, the model was basic. Now, we used real data and checked it on the ground,” Shanu shares.
The study findings point to an increasingly fragmented landscape. Forest patches remain, but they are more isolated, separated by human-dominated areas. The study notes that between 2005 and 2015, forest cover declined from about 40% to 35%, primarily due to an increase in agricultural land, particularly in the Balaghat and Chhattisgarh Forest divisions, driven by human settlements and economic expansion.
“People talk about habitat patches, but not enough about the land between them,” Shanu noted. “Villages, roads, and small forest areas in between are just as important.”
This fragmentation restricts connectivity and isolates populations. Over time, it reduces genetic exchange and increases vulnerability to local threats. A 2013 genetic study had already warned that connectivity in the Satpura-Maikal region depended on functioning corridors — the same corridors now under pressure.
Mapping habitat and connectivity
Shanu’s study also assessed what makes an area suitable for tigers. Habitat quality depends on factors such as prey availability, water sources, vegetation cover, and distance from human disturbance. Using data on prey species such as sambar, chital, wild boar, and nilgai (blue bull), the researchers created habitat-suitability maps. These maps revealed that only a relatively small portion of the landscape remains highly suitable, largely within dense forest areas such as Balaghat and the Kanha-Achanakmar region.
To understand how these areas are linked, the team treated the landscape as a network of habitat patches connected by potential movement routes, which highlights the patches most critical for maintaining connectivity. One corridor — the stretch linking Pench, Kanha, and Achanakmar — appeared to be a key tiger dispersal route in central India. “If these corridors are damaged, links across the region can break down,” Shanu says. Meanwhile Indravati appears more isolated, raising concerns about long-term population stability.
The study found that 46% of the landscape is poorly suited for tigers, while only about 18% is highly suitable habitat.
Field surveys helped validate these findings, with researchers recording signs of animal presence and comparing them against model predictions. The game theory model showed that tigers prefer landscapes with abundant prey, dense forests, water sources and fewer human disturbances.
The study also modeled how tigers choose their routes, weighing prey availability against risks such as roads and settlements. It identifies anthropogenic disturbances — such as roads, settlements, and railways — as significant barriers that lower the connectivity payoff for tigers. Among prey species, nilgai and chital exhibited the highest suitable habitat coverage.
Implications for conservation
The study findings highlight that tiger conservation cannot stop at the boundaries of protected areas. While reserves remain essential, the surrounding landscape plays a crucial role in keeping populations connected.
Protecting key corridors, especially the Pench-Kanha-Achanakmar link, will be vital. Limiting new development, restoring degraded forest patches, and strengthening buffer zones could improve connectivity. Where roads intersect movement routes, wildlife crossings, roadkill monitoring and better traffic management may help reduce collisions.
“Restoration of degraded corridors using native vegetation and community engagement in buffer zones can also reduce habitat fragmentation effects, enhancing functional connectivity,” the study recommends, while also adding that policy frameworks should “mandate environmental impact assessments for infrastructure projects in these landscapes.”
Local communities are also central to these efforts. Many live within or near corridors and are directly affected by both wildlife presence and conservation policies. “Local communities are often supportive of conservation. But they need to be involved properly and given a role,” Shanu says.
The researchers also acknowledge the limits of their model. Its accuracy depends on data quality, and tiger behaviour varies with local conditions. “Better data gives better results,” Shanu notes, highlighting the need for more GPS tracking and field verification. The study also calls for stronger monitoring systems to track both habitat change and wildlife dynamics. “We talk about smart cities, but not smart forests. The tools exist. They just need to be used with the same focus towards the landscapes that the wildlife depend on,” he adds.
Banner image: A male tiger at a stream in Kanha Tiger Reserve, Madhya Pradesh. Image by Yajuvendraupadhyaya via Wikimedia Commons (CC BY-SA 4.0).
Read more: A recovering tiger population powered by forest corridors
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