The Wildlife Institute of India is presently engaged in a nationwide estimate of tigers the 28 tiger reserves in India. WII is an autonomous research institution under the aegis of the Union Ministry of Environment and Forests. The final count is expected to be announced on 31 December 2007.
Why a tiger census?
The Sariska slaughter of 22 tigers some years back brought to light the exaggeration of tiger numbers. Never before was there so much pressure on forest administration to give an accurate picture. The question in Sariska was, were there really 22 tigers that fell to the poachers' bullets? Or were there only 16 to 18 tigers as it was suggested by a field director of the reserve - Deepak Bhatnagar when he sought a recount in 2004.
Because tiger presence and tiger numbers quantify habitat conservation itself, over the years, the tiger census has come to manifest accountability of the forest officials. The tiger is at the head of the faunal pyramid in Protected Areas. If the numbers are healthy, they also reveal that their prey base too is in good numbers, proportionate to the health of the ecosystem.
This is because The Wildlife Protection Act 1972 stipulates the recovery of material to prove the case in a court of law. "Collection of evidence is tedious because material decomposes after a while, scattering of evidence might not be easy to connect to poaching case in question; so providing the witness becomes very challenging. Only investigations can produce results, but for such things documentary evidence will sustain the case," says P S Somashekhar, the field director of the Sariska Tiger Reserve.
Forest officials were helpless in proving poaching because of the challenges associated with recovery of material. It was easier for them to inflate numbers instead of pursuing laborious investigations which would in any case prove fruitless in a court of law.
Feeling vulnerable about the allegation that forest officials exaggerated tiger numbers, a former field director of Ranthambhore Tiger Reserve - G V Reddy says, "We used the techniques of tiger census known then, but I had made it very transparent by inviting volunteers from all walks of life and did it openly and sent the detailed figures and analysis to the Head of the Department."
How are tigers counted?
There are a number of different methods of tiger census in vogue. These are the pugmark, DNA analysis, biometric data analysis, block counting, radio collaring, digital pugmark prey base indicators, etc. The cheapest or most cost effective method remains the pugmark technique. It entails searching for tiger pugmarks on the forest floor; placing a glass plate on it, and drawing with the felt pen the outlines of the pugmark as seen through the glass pane. Forest guards later make a mould conforming to the outlines of the pugmark. The moulds are then analysed to check for the gender and age of the tiger. Guards recorded the data pertaining to location, territory, time of sighting, and how old the pugmark is at the time of moulding on-site.
The human element and propensity for human errors perhaps explains the glaring gaps in tiger counts confirmed heretofore by the forest departments in the different states. "There was nothing wrong at all with the pugmark technique, only its interpretation was," clarifies Dr Y V Jhala, senior wildlife biologist at the Wildlife Institute of India in Dehra Dun.
However the radio collaring method for tiger census is by far the safest but perhaps most expensive method, because with radio collaring what you see is what you get. Radio collaring is an accepted best practice in the science of wildlife biology the world over. In Canada, polar bears are collared, so are rhinos and cheetahs in many African countries like South Africa, Kenya and Namibia.
Revamping the approach to counting
To address the shortfalls of the pugmark monitoring system, the Project Tiger Directorate (currently the National Tiger Conservation Authority) commenced a project in collaboration with the Wildlife Institute of India and the Forest Department of Madhya Pradesh in 2003 to evolve a monitoring program for tigers, co-predators, prey and their habitat in the Satpura-Maikal Landscape. This pilot project evolved field friendly data collection protocols in consultation with field managers and scientists. The monitoring program uses remote sensing, geographic information system, and global positioning system technology in combination with high resolution spatial data and field data, based on sign surveys, camera trapping, and distance sampling, to effectively monitor tiger and prey populations.
Following the Sariska crisis, the Tiger Task Force recommended the implementation of this monitoring scheme for all tiger occupied landscapes.
As noted at the beginning, WII is expected to announce its final estimate on 31 December 2007. According to the WII, the Project Tiger Directorate synergised this mammoth task by liaisoning with the state government's forest departments to generate the required field data in appropriate formats. The Wildlife Institute of India has imparted training in field data collection, and for estimating tiger and prey densities for the nationwide monitoring program. The data and inferences generated by the system would not only serve as a monitoring tool but also as an information base for decision making for land use planning.
The preliminary report of the WII has thrown up some numbers. The WII estimates that there are 296 tigers in Madhya Pradesh with a lower limit being 228 and an upper limit of 364 tigers. In Maharashtra there are 103 tigers according to the estimate with the lower limit being 76 and upper limit estimated at 131 tigers. In Rajasthan the estimate for optimum tiger presence was 32 but 3 tiger cubs died over a 3 week period between May and June 2007 bringing down the number to 29. Optimum alludes to the extrapolation that a particular forest beat can support only so many tigers because there is only so much habitat for so much of prey base. (Given the territorial nature of the fascinating felines, the optimum number for Rajasthan seems plausible. Locals in the town of Ranthambhore say there were never more than 35 tigers in Ranthambhore Tiger Reserve whereas the forest officials had reported 46 tigers.)
In Chattisgarh the estimated tiger number is 26 with the lower limit being 23 and 28 the upper limit. Further, tiger presence has been recorded in 208 beats in Andhra Pradesh, 66 beats in Chattisgarh, 489 beats in Madhya Pradesh, 445 beats in Maharashtra, and 340 beats in Orissa.
The preliminary report of the WII vindicates the prey base theory propounded by Dr Ullas Karanth - wildlife biologist and tiger researcher of the Wildlife Conservation Society of New York. Karanth and other researchers had in 2004 itself propounded the prey base theory modeling tiger numbers on the available densities of prey base in a given Protected Area.
Despite the revamped approach, however, the picture released by the WII may be incomplete. WII is undertaking the exercise only in the 28 notified tiger reserves and leaving out other PAs. The northern most tiger reserve in India is Corbett Tiger Reserve in Uttaranchal, so logic begs an answer if there are no tigers at all to be found roaming in wildlife sanctuaries - which are not notified as tiger reserves -- of Himachal Pradesh, and Sikkim, Higher Nilgiris, Bhimgad in the Western Ghats, Eastern Ghats where there are unconfirmed reports of sighting of tigers. The error margin can also be wide given that tigers are territorial and their presence have been recorded in far more beats than where the tigers were sighted and documented. A forest beat is an administrative reference to areas that are patrolled by 'beat' forest guards.
Census likely to sharpen debate on resettling forest dwellers
A stark observation of the preliminary WII report is that the tigers' presence has been documented largely in core areas without any kind of anthropogenic or human induced pressure. In other words it means tigers are surviving only in those places where there is minimal human induced disturbance and a large thriving population of its prey base.
"The principle components that significantly contributed to explaining variation in tiger densities were primarily those containing information on tiger sign indices, prey indices, anthropogenic disturbances and wilderness values," says the preliminary report. The heartening factor is that the tiger also protects the habitat for leopards, wild dogs, Sloth Bear, Cheetal, Sambhar, wild boars, Indian Gaur, and Nilgai in the beats that have been studied.
The WII report expected on the 31 of December 2007 ought to serve as a guideline to formulate policies of land use as well as accentuate the debate on rehabilitation of forest dwellers in favour of wildlife conservation.