States are increasingly translocating herbivores and ungulates to reserves to ensure adequate prey base for tigers. But this strategy may not prove sustainable for long
Photograph: Dharmendra Khandal Since October 2023, there has been a flurry of activity at the Palamu Tiger Reserve in Jharkhand. The officials have undergone training from the Madhya Pradesh forest department and a customised transport vehicle has been arranged to bring 300 herbivores from the Bhagwan Birsa Biological Park in Ormanjhi village, Ranchi, 192 km away. All that is awaited is approval from the Central Zoo Authority to bring the 250 spotted deer, 20 black bucks, 10 barking deer, 10 sambar and 10 nilgai, says Kumar Ashish, deputy director, Palamu Tiger Reserve (South).
The National Tiger Conservation Authority (NTCA) has already approved this plan, a first for Jharkhand. Ashish says the herbivores will first be moved to a fenced enclosure at Palamu, so they can acclimatise to the area and officials can monitor their health. After a month, they will be released as tiger prey.
The prey base, or the animals that serve as food for predators, for tigers includes spotted deer, gaur, wild boar, nilgai and sambar. “In the eight ranges of Palamu, only one has 5,000 deer while the rest have 100-200 deer each, along with other animals. The reserve has three tigers. A tiger consumes about 50 chital-sized animals in a year, and so requires 500-600 deer that continually reproduce,” Ashish explains. “Prey density, or the number of available prey per square kilometre, for tigers should be around 25. Currently, it is four,” he adds. The reserve plans to raise its tiger numbers to 15-20, necessitating 25,000 deer.
Translocation of prey may be planned in Jharkhand for the first time, but states like Madhya Pradesh, Karnataka, Maharashtra and Telangana have been reporting such exercises over the last decade. “It has increased in recent years,” says Hemant Singh, Assistant Inspector General of Forests at NTCA. Forest officials say that the reason for this is shortage of food for tigers and other predators. The prey base is depleted due to habitat destruction, poaching and hunting for bushmeat and encroachment.
As per the “Status of Tigers—co-predators and prey in India, 2022” report by NTCA, India has 3,682 tigers in 53 reserves across 18 states, an increase from 2,967 tigers in 2018. While numbers for prey in 2022 are not available, earlier estimates suggest disparities across reserves. As of 2018, Ranthambore, Rajasthan had 55 tigers. Individual density (occurrence of individual species) of chital was 21.62 per sq km and sambar was 13.95 per sq km. The state’s Mukundara Tiger Reserve had no chital density, but individual density of nilgai was 3.59 per sq km and chinkara was 2.05 per sq km.
Ashish explains that on average, a male tiger needs a territorial area of 30 sq km and a female needs 10 sq km. However, territories can differ due to geographic location, vegetation and available prey density. If the prey density is smaller, the tiger will travel farther in search of food. “It may venture into human habitations, increasing the possibility of human-tiger conflict,” he says. So, human intervention is needed to augment prey base.
At the Satpura Tiger reserve in Madhya Pradesh, the individual density of chital is 4.24 per sq km, barking deer is 2.49 sq km, sambar is 6.48 per sq km and nilgai is 2.56 per sq km, say the 2018 estimates. L Krishnamurthy, field director at the reserve, says the low prey base could be due to increasing biotic pressures like grazing, collection of fuel, small timber, minor forest produce, drawdown agriculture in the backwaters and fishing.
Apart from the basic objective of feeding the big cats, prey augmentation also helps conserve biodiversity. “Satpura has good population density of gaur, sambar, nilgai and wild pigs, but less chital. Having animals of different species helps maintain the food chain and encourages habitat conservation,” he says, adding, “Hence, sometimes animals are moved from high-density areas to low-density regions to maintain prey base and population density.”
Translocation helps the zoological parks as well. “Herbivores breed in abundance in zoological parks, in the absence of any natural predator. Moving these animals in the wild becomes imperative to avoid conflict and inbreeding,” says a forest department official from Telangana, on the condition of anonymity.
Though prey translocation has proven useful, experts say it is counterproductive to scientific conservation. Y V Jhala, former dean at the Wildlife Institute of India, Dehradun, says, “With the boma technique adopted from South Africa, which has no tranquilisation, there is less mortality. This has led to a more than 90 per cent success rate in translocation.” However, he highlights that herbivores and ungulates translocated from parks have never lived in the wild and their anti-predatory responses are weak. Adds Dharmendra Khandal, conservation biologist with Tiger Watch in Ranthambore, “These herbivores will face difficulties in finding safer zones.” Artificial prey augmentation is not conservation, but population sustenance and management, he says.
Ravi Chellam, chief executive of Metastring Foundation, Bengaluru, and coordinator of Biodiversity Collaborative, says the approach for augmenting prey base is expensive and flawed. “It is not about feeding the tigers with excess prey bred in captivity. Translocation must be carefully implemented considering factors such as how long the animals have been in the park or reserve, sex ratio, age group and size,” he says.
K Ullas Karanth, director of the non-profit Wildlife Conservation Society’s India Programme and a tiger expert, says protecting habitats from encroachments and degradation will allow prey densities to increase with time. “We are feeding these tigers in a national park rather than in a zoo. Such attempts, along with speeding up natural recovery or raising tiger and prey densities above natural levels are unscientific and often the cause of increase in human wildlife-conflict. They can also have deleterious impact on other forms of biodiversity. There is no research to support the need for such actions,” he says.
“About 75 per cent of potential tiger habitats—for example, all of Odisha, Jharkhand and Chhattisgarh—do not have tiger populations at reasonable natural density,” he adds. As per the 2022 NTCA report, 11 reserves recorded one or no tiger. “On the other hand, reserves such as Bandipur, Nagarhole and Tadoba have high tiger density. Artificially adding prey could lead to conflicts between tigers,” he says.
DO CHEETAHS HAVE PREYAvailability of prey is not just a concern for wild tigers in India, but also for the group of African cheetahs introduced at the Kuno National Park in Madhya Pradesh since 2022, to revive populations of the big cat in the country.Cheetahs commonly prey upon ungulates and herbivores such as deer species and hares. The “Action Plan for Introduction of Cheetah in India” report, released in January 2022 by the Wildlife Institute of India, the National Tiger Conservation Authority (NTCA) and the Madhya Pradesh forest department, says that Kuno has an overall potential prey species density of 51.58 individuals per sq km, including a prey density of 38.48 chital per sq km. However, on October 27, 2023, the Cheetah Project Steering Committee constituted by NTCA to review the initiative, revealed that no cheetahs will be released in the wild unless the prey base is increased to 35 individuals per sq km and must ideally be 50 individuals per sq km. This highlighted concerns on the potential scarcity of prey at the national park. Negating such claims, Uttam Sharma, chief conservator of forests at Kuno, tells Down To Earth that there have been no issues with the prey base at Kuno. A prey base assessment is carried out regularly, he says. |
This was first published in the 1-15 February, 2024 print edition of Down To Earth
We are a voice to you; you have been a support to us. Together we build journalism that is independent, credible and fearless. You can further help us by making a donation. This will mean a lot for our ability to bring you news, perspectives and analysis from the ground so that we can make change together.
.png)
Comments are moderated and will be published only after the site moderator’s approval. Please use a genuine email ID and provide your name. Selected comments may also be used in the ‘Letters’ section of the Down To Earth print edition.