- In 2009, Panna Tiger Reserve reintroduced tigers after extensive poaching wiped them out locally. Researchers began tracking how these big cats would adapt and interact in a shared space.
- Over 10 years, they documented 126 tiger pairs and found that while males mostly avoided each other, female relatives often shared space, and mating patterns suggested they avoided inbreeding.
- Findings show that phased reintroductions, mother-cub bonds, and fine-scale behavioural data are critical to the success of such reintroduction projects.
Tigers are often considered to be solitary creatures, prowling through the forest and defending their territories fiercely. But what happens when they are reintroduced into a new wild region where they have gone locally extinct? How do they interact when forced to share a new space?
“Since childhood, we have been taught that tigers do not exhibit group-living behaviour. However, the frequency and nature of their interactions, whether positive or antagonistic, have rarely been assessed quantitatively. Questions have remained about whether tigers possess a rudimentary social network or form weak, temporary social bonds,” says Supratim Dutta, research scholar at the Wildlife Institute of India (WII).
To address this gap, Dutta and Ramesh Krishnamurthy, a scientist at the WII, conducted a decade-long study in Panna Tiger Reserve (PTR) in Madhya Pradesh. Their findings are beginning to answer those long-standing questions, suggesting that tiger society may be far more complex than we thought.
The Panna experiment
In the early 2000s, Panna’s tigers disappeared. Rampant poaching, poor protection, and mounting human pressures had wiped them out entirely. By 2009, it was clear that PTR needed drastic action. A reintroduction project began, and tigers from reserves such as Kanha and Pench were brought in to repopulate the area.
“The tiger in Panna was extinct only for a couple of years and the prey base was intact. It was a targeted poaching event that removed tigers from the system, not ecological collapse. So, the missing element [tigers] was simply returned,” says Yadvendradev Jhala, an Indian National Science Academy (INSA) senior scientist, National Centre for Biological Sciences, Bengaluru, and Wildlife Institute of India, Dehradun.
From 2009 to 2019, the researchers tracked 13 reintroduced tigers using a combination of GPS and VHF (very high frequency) collars to understand whether the big cats crossed paths to mate, shared kills, patrolled overlapping territories, or deliberately avoided one another. These interactions, called intraspecific interactions, are key to understanding mating patterns, survival strategies, and social tolerance.
But sustaining such telemetry tracking via collars for over a decade in Panna’s dense, rugged landscape posed numerous technical and logistical challenges. “VHF collars are affordable with long battery life, making them ideal for monitoring female tigers with smaller ranges, but they require constant field effort; demand a dedicated field team for continuous tracking. Males roam widely, making their signals harder to track in difficult terrain,” explains Dutta. “GPS collars provide detailed location data with less effort but have shorter battery life and sometimes miss signals, especially in dense forests or during monsoon season, leading to data gaps.” Using both collar types allowed the team to balance detail and duration.
The team measured two kinds of contact: static interactions (where home ranges overlapped) and dynamic interactions (where tigers were in the same place at the same time). To analyse behavioural tendencies, the team also applied Benhamou’s IAB (Index of Attraction or Avoidance Between Individuals), a method that factors in both time and space.
The index was used at 100-metre and 500-metre distance thresholds to identify whether tiger pairs were consistently closer or farther apart than expected, allowing researchers to determine if individual tigers were showing signs of attraction or avoidance. Year-wise analysis of these patterns helped the team understand how tiger relationships evolved over time.
What the data revealed
The researchers identified 126 distinct “dyads” or tiger pairs ranging across male-male (18), female-female (35), and male-female (73) combinations. What emerged was a nuanced picture of tiger society, revealing three striking patterns.
Males avoided each other. They rarely moved together, even when their territories overlapped. Their paths intersected in space, but not in time. “Subordinate males typically avoided dominant individuals by maintaining spatial separation. Their movements appeared to be largely independent of one another,” says Dutta. This avoidance likely reduces the risk of direct confrontation.
Female tigers, especially mothers and daughters or sisters, on the other hand, showed higher social tolerance. Young males dispersed widely, but young females often stayed near their natal areas, a behaviour called philopatry. These females shared space with their mothers until they were ready to establish their own territories.
“By establishing a territory near their mother’s, female tigers avoid the risks of long-distance dispersal, such as unfamiliar terrain or threats from other carnivores,” says Dutta. “They also benefit from knowing the location of water, prey, and shelter.” This behaviour fosters kin-based tolerance, lowers aggression, and improves survival. In fact, studies from Panna found that philopatric females had significantly higher survival rates (~84%) compared to those that dispersed farther.
Lastly, male and female tigers often had overlapping home ranges, but actual movement together was rare outside mating periods. Some females were observed returning to the same male partners across years, suggesting selective mate preferences. Crucially, researchers found no evidence of mating between close relatives among the tracked tigers, indicating an innate mechanism for avoiding inbreeding, which is essential for maintaining genetic health in a reintroduced population.
Implications for conservation
The findings from Panna offer vital lessons for tiger conservation and reintroduction efforts elsewhere.
For instance, reintroductions must be timed and phased. “It works best when done early, before the ecosystem degrades or changes significantly,” says Jhala. “In Panna, the prey base and habitat remained intact, so we could reintroduce tigers without altering the ecological balance.”
Additionally, the researchers recommend phased releases, introducing one or two individuals at a time rather than many at once. “This prevents dominance-related aggression, allows time for mate selection, and preserves genetic diversity,” says Dutta.
The study showed that overlapping ranges do not mean interaction. By combining static and dynamic data with IAB analysis, it moved beyond assumptions and confirmed actual behavioural patterns. This approach can help conservationists interpret maps, focusing not just on territory, but on relationships.
It also found that maternal bonds are crucial. The near two-year learning period between mother and cub is critical for survival. Cubs learn to hunt, navigate terrain, and avoid danger. “Recognising the value of these bonds can shape translocation protocols, ensuring that cubs are not separated prematurely and that family groups are carefully managed,” says Dutta.
Looking ahead
The study had its limitations. Not all tigers in Panna were collared, so some interactions, especially with unmonitored individuals, remain undocumented. GPS signals can also be interrupted in rugged terrain, creating data gaps.
Also, while tigers are often seen as solitary, their presence influences and is influenced by a complex web of ecological relationships. In Panna, where leopards, wolves, hyenas, jackals, and other predators also roam, tiger movement patterns could be impacting other aspects, such as prey distribution or predator activity. Researchers also noted that environmental factors such as temperature, water availability, and even lunar cycles could be shaping their interactions.
Still, the study marks a major leap forward in understanding tiger behaviour. Looking ahead, the researchers hope to expand monitoring to include multiple species. Comparing their spatial dynamics could offer deeper insight into how reintroduced apex predators reshape entire ecosystems.
Read more: Teething troubles or conservation challenges at India’s latest tiger reserve?
Banner image: Female tigers establish territories near their mothers to avoid the risks of long-distance dispersal, and benefit from knowing the location of water, prey, and shelter. Image by Supratim Dutta.
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