By Dr. Aniruddha Majumder, Dr. Kalyanasundaram Sankar and Dr. Khageswar Naik
An insight into the secret family life of a remarkable Pench tigress
The scorching summer morning was not an ideal day to be outdoors. The three of us were exhausted, worn down by the heat as we huddled close on the dusty, deciduous forest floor. We were in the Pench Tiger Reserve, Madhya Pradesh, watching four 18-month-old tiger cubs that had seemingly been abandoned by their mother for over five days now. They seemed to be growing weak, their eyes tired with hunger.
Between April 2007 and December 2012, we had radio-collared four tigers (an adult male-T2, an adult female-T15 and two sub-adults-T-31 and T-39) in Pench. These radio-collared cats were then regularly monitored using camp elephants. The cubs we were watching belonged to T-15, or Collarwali (one with a collar) as she was popularly referred to by visitors to Pench. Collarwali, herself, was one of four cubs of yet another famous tigress ‘Barimada’ – featured in the celebrated BBC documentary ‘Spy in the Jungle’
Even as a cub, Collarwali had been regularly monitored through her non-radio collared mother Barimada, using camp elephants. Collarwali was the first of Barimada’s four cubs to set out on her own and establish her territory in the prime area of her mother’s range. Her sister, popularly called the ‘Baghinnalawali female’ established her territory partially overlapping Barimada’s on the fringes of the Karmajhiri range. T-31, one of Collarwali’s brothers, finally settled in the Pench Mowgli Wildlife Sanctuary and the other brother, T-17, was last sighted in the Pench Tiger Reserve in September 2009.
We estimated the minimum natal or growing area of Collarwali’s and her siblings between May 2006 and June 2007 as 23.9 sq. km. Most of this fell within prime chital habitats of the park. Although Barimada began taking her cubs along with her on hunting trips by the time they were a year old, the lack of hunting expertise meant the cubs took almost five full months to hone their hunting techniques, which resulted in their bringing down an adult female wild pig. They started off by catching chital fawns and then progressed to adult deer (70 per cent of Collarwali and her siblings’ diet). Of course, common langurs, wild pigs and sambar deer were also predated. What always amazed us was how these tigers skillfully killed and consumed porcupines without hurting themselves. We watched with delight as this tiger family evolved into consistently successful hunters with young Collarwali, the most expert among them.
Collarwali reunited with her four cubs from her second litter after staying away from them for 16 days. The smart tigress was protecting her cubs by keeping the male tiger T-30 at bay. Though she kept away, she ensured their survival by leaving them in an area with an abundance of food and water, adequate cover to stalk and rest and importantly, no human disturbance.
Photo:Dr. Aniruddha Majumder
She littered for the first time in May 2008, when three beautiful cubs emerged. An inexperienced mother, she was unable to protect her cubs from the harsh monsoon rains and her newborns died of pneumonia within three months. In October 2008, Collarwali produced her second litter. This time four cubs were born, three of which were male. It was this lot that we were watching and we were terrified that this litter too might be lost since the cubs were growing weaker and hungrier, with no sign of Collarwali on the horizon. It was the fifth day that she was away from her cubs. Should we intervene, we wondered? Was live bait called for? Park veterinarian, Dr. Akhilesh Mishra, felt that the cubs were looking weak and dehydrated on account of the scorching summer. Gautam Soni and Santosh Patel, park frontline staff, opined that even Barimada had kept away from Collarwali and her siblings, possibly to force them to hunt independently.
We did not have the facilities then to monitor Barimada and had no way of knowing whether she was meeting her cubs at night. This time, we were better prepared. We radio-collared one of Collarwali’s male cubs, T-39, and followed the little one throughout the next night. We kept a fair distance from them so as not to affect their natural behaviour. Half an hour before midnight, they came to the Pench river, where they stopped for a drink. Collarwali, we knew, was at that very moment, close to the foot of Kalapahar, the highest peak in Pench. They were separated by a distance of 1.5 km. A tiny sliver of hope arose in our hearts at the possibility of a union between mother and cubs. But Collarwali chose to move ahead, creating an even greater distance between her and the cubs. Disappointed, we returned to base camp, but set out again early the next morning, this time on an elephant. We discovered that the cubs had still not made a kill and were growing worryingly weaker. Collarwali was again spotted at a distance of 1.5 km. She had hunted an adult female sambar deer. Would she return to her cubs and take them to feast on the kill? We monitored the family throughout the day and at night. Neither did she return to her cubs nor did she call them to her. All our presumptions about tigers were being tested by her lack of interest in her cubs!
Then came the twist in the tale!
Collarwali littered for the first time in May 2008. The inexperienced mother was unable to protect her cubs from the harsh monsoon rains and her newborns died of pneumonia within three months. Her subsequent three litters have fared much better, with cubs from two litters having independently established territories. The fourth litter of three cubs are currently with Collarwali.
Photo:Dr. Aniruddha Majumder
Collarwali was spotted with the male tiger T-30. He, it seemed, had overtaken most of the territory of T-2, the father of these cubs, after his death. The pieces of this unsolved puzzle now fell in place. Collarwali was protecting her cubs by keeping T-30 at bay. The next morning T-39 finally hunted down a wild pig. It was a gratifying sight to see the four cubs feeding on the kill without fighting, even though they must have been unbearably hungry. They polished off the kill in two and a half hours and then made their way to the Pench river to quench their thirst, resting under Lantana bushes while their mother cavorted with T-30 where she had made her kill the previous day.
In the evening, Collarwali was spotted alone. At about seven p.m., she went to the Bizamatta talab for a drink although the Pench river was closer. More than 40 per cent of the kill she had made was intact and we wondered if she might bring her cubs to feed on it. Another night passed. The next morning Pench came alive with bird song, and the sun filled the forest with its glitter! The cubs were at the top of Chitalpahari, a hillock in the Gumtara Range. T-39 and one of his brothers descended the hillock and headed to the Pench river later, where they rested all day in the shade of Lantana bushes. At dusk, T-39 killed a sub-adult female chital for his family. The next morning, we found the four cubs two kilometres away from Collarwali. We received signals from both Collarwali and T-39 every 30 minutes, always from opposite directions. Days passed by but Collarwali did not join her cubs. The cubs hunted down two more chital females in the next two days close to the Pench river. The mother had kept away from her cubs for over a fortnight.
Collarwali was a smart tigress. She had left her cubs in an area where the habitat was rich in prey species and within 100 m. from the Pench river. There were four caves at Chitalpahari, where the cubs could find shelter and safety. There was no human disturbance and we did not notice any other tiger close to the cubs’ hide-out during the entire period of our investigation. The forest was richly laden with dry deciduous teak Tectona grandis trees along with green leafy trees such as pakhar Ficus infectoria, kusum Schleichera oleosa, jamun Syzygium cumini and tinsa Ougenia dalbergoides that provided protective cover. It was the diversity of the habitat that supported the high density of browsers and grazers such as sambar and chital there. The grass Cynodon dactylon patches along the inundated areas of the Pench reservoir offered ideal feeding grounds for the wild pigs and chital in summer.
Dr. Aniruddha Majumder (right) and Dr. Kalyanasundaram Sankar with Collarwali or T-15, one of four cubs of the famous Barimada tigress. Between April 2007 and December 2012, four tigers (an adult male-T2, an adult female-T15 and two sub-adults-T-31 and T-39) were radio-collared in Pench and then regularly monitored using camp elephants.
Photo Courtesy:Dr. Aniruddha Majumder
On the morning of the 16th day at around 4.30 a.m., we woke to Collarwali’s roaring, which echoed across both Chitalpahari and Kalapahar. She was on the open river bank of the Pench river. And we were at the Golpahari patrolling camp. Ten minutes later, there was a response from the opposite bank of the river. Collarwali had probably made a kill and was calling her cubs to feed on it. From 5 a.m., the radio signals from both Collarwali and T-39 began emerging from the same direction. We waited with bated breath for the sun to rise and for the camp elephant to arrive. Aniruddha began tracking the signals from an open vehicle and finally reached a point close to their probable location. At around 5.30 a.m., the Range Officer, B.P Tewari, instructed the camp elephants to move toward the Pench river bank. We drew closer and finally spotted the cubs with their mother. They were feeding on a chital kill, which they took nearly three hours to finish. After this union, Collarwali took her cubs over to the ‘Number Two Lantana’, situated at the Alikatta forest beat, where the family rested.
Our entire team was ecstatic and relieved, for after 16 days of continuous monitoring, we finally saw the mother and her cubs together. We continued tracking them and observed how Collarwali kept training her cubs until they were ready to disperse. In December 2010, the radio-collared male T-39, moved over 50 km. away from his natal area into the fringes of the reserve.
Collarwali used 44.3 per cent (10.6 sq. km.) of her natal area to raise the second litter and 46.4 per cent (10 sq. km.) for her third litter. Most of this fell within prime chital habitats of the park. Apart from chital, their diet also included common langur, wild pig, sambar deer and porcupine. The mother keeping herself away periodically to encourage sub-adult offspring to hunt independently is clearly a survival strategy for tigers prior to their dispersal.
On July 6 and 7, 2010 Collarwali mated with T-30, the tiger from whom she had to protect her cubs. On October 23, 2010, after a gestation period of approximately 107 days, she gave birth to five cubs. Four of these were females. Female cubs are mostly philopatric, which is to say that they stay close to their birth place. Collarwali’s denning site for her third litter was identical to that of her second. In all, Collarwali used 12 sites to rear her three litters (three den sites for the first, four for the second and five for the third). Her first litter was born in a small cave at Kalapahar, her second and third at ‘Number Two Lantana’.
The habitat where Collarwali’s first litter was born was very similar to that of Barimada’s. Collarwali never shifted her cubs from any of her litters for the first 15-20 days, then kept shifting them from den to den, all within a distance of under 200 m. and in thick forests with no human disturbance. Every den site was under 250 m. from a reliable and safe water source in any season. We also observed that the wild prey density around her den sites was high; around 348.2 per sq. km. (chital – 176.8 per sq. km., sambar – 10.6 per sq. km., common langur –144.5 per sq. km., nilgai – 2.3 per sq. km., wild pig – 12.2 per sq. km., gaur 1.5 per sq. km.). To figure out how much food they could potentially access, we estimated the total biomass to be 12,384.7 kg. per sq. km.
Collarwali began taking her third litter out of their den much sooner than her previous litters. Probably the presence of their father T-30, the resident male, offered additional protection. Her own father, T1, fondly called the ‘Charger of Pench’, had offered similar protection to Collarwali and her siblings as they were growing up.
When the five cubs of her third litter were just two months old, we spotted them crossing the Pench river with their mother. For the first two months, she mostly hunted sambar, which she killed once every three days and on most occasions we found T-30 at the kill with her. With so many hungry mouths to feed, it is not surprising that she chose to bring down large prey, including one nilgai. And her third litter learned to hunt faster than her earlier offspring. They were just 14 months old when a female cub hunted a chital fawn on her own. The cubs largely fed on soft meat in the first six months of their life. And in the pre-dispersal stage, when they were around 20 to 24 months old, they began forming groups. This was probably to avoid being spotted easily by the prey species in the deciduous forest. The male cub teamed up with one of the female cubs and the remaining three female cubs formed the second group.
Collarwali’s third litter was fathered by T-30, the very male she had to protect her second litter from. This litter learned to hunt faster than her earlier offspring. They were just 14 months old when this female cub hunted a chital fawn on her own. The cubs largely fed on soft meat in the first six months of their life.
Keeping herself away periodically to encourage sub-adult offspring to hunt independently is clearly a survival strategy for tigers prior to their dispersal. We noticed that at this stage over 65 per cent of their kills comprised chital. We estimated that Collarwali’s home range extended to over 29 sq. km. in the duration that she gave birth to her cubs until they dispersed. The corresponding figure for the third litter was 28 sq. km. Unfortunately, we were not able to assess the size of Collarwali’s home range when she raised her first litter. We do know, however, that she used 44.3 per cent (10.6 sq. km.) of her natal area to raise the second litter and 46.4 per cent (10 sq. km.) for her third litter. Her success had everything to do with her choice of denning areas, which met all the requirements for survival such as the abundance of food and water, adequate cover to stalk and rest and, importantly, little or no human disturbance.
Under their mother’s tutelage, all the cubs from Collarwali’s third litter have now gone their separate ways, independently establishing territories and carrying on their quest for survival. Our camera trap study revealed their movements in the Pench forest between December 2012 and February 2013. In May 2012, Collarwali gave birth to a fourth litter of three cubs, which are moving along with their mother as Sanctuary readers read this account.
Despite its connectivity with the Pench forests of Maharashtra, the Madhya Pradesh forests protected as the Pench Tiger Reserve are still relatively small. And it is vital that this critical nursery is kept isolated, and protected and is monitored to the highest standards. Equally important is the need to ensure that when they disperse, young tigers are not forced to rely on livestock, which would automatically lead to human-animal conflict. In return, the entire mix of life in such landscapes will gift us with invaluable ecosystems services that include fresh water, carbon sequestration and climate moderation… all critical to human survival.
Dr. Aniruddha Majumder and Dr. Kalyanasundaram Sankar are associated with the Wildlife Institute of India, Dehradun, while Dr. Khageswar Naik is the former Field Director, Pench Tiger Reserve, Madhya Pradesh.