REVIVING THREATENED TIGER POPULATION IN THE WESTERN RAJAJI NATIONAL PARK

Vinod Rishi

Fig !

 Fig 2

THE TIGER CRISIS IN WESTERN RAJAJI NATIONAL PARK:

            Rajaji National Park (RNP) is, at present, the north-western limit of the distribution of the Indian tiger, Panthera tigris tigris, in the world. The latest officially estimated population of tigers, based on statistical modeling approach, in Rajaji National Park (820 sq km) is between 8 and 15*.

The river Ganges bifurcates RNP into two sections of 249 sq km (Chilla Wildlife Sanctuary) east of the river Ganges, and 571 sq km (Rajaji and Motichur Sanctuaries) west of the Ganges. The tenuous link (Chilla-Motichur corridor) between the two sections of the National Park has been virtually blocked for tiger movement. A month-wise seven month (October 2008-April 2009) monitoring of tigers was carried out with the help of the Director, RNP. In the maps red wash indicates tigers; there were three tigers – one in Dholkhand and two in Kansrao-Motichur forests. Fig 1 illustrates the situation in April 2009, for one month only; earlier months showed the tigers in the neighboring beats from time to time. The spatial relationship of the three tigers has not changed much even today. The 2011 report confirmed by statistical methods the existence of three tigers in western RNP: one in Dholkhand and two in Kansrao-Motichur complex, just as it appeared in monthly maps of October 2008 to April 2009. The rest of the estimated tiger population inhabits the 249 sq km Chilla Wildlife Sanctuary east of the Ganges; this population has an active genetic link with the Lansdowne-Kalagarh-Corbett-Haldwani tiger population, and is not genetically threatened.

All three in the western RNP are tigresses – two siblings born in Kansrao Range in 2003, and their mother. The presence of the two siblings with their mother was first noticed in March 2003 on a water-hole in a dry nullah that flowed under a wooden bridge on the road through Kansrao forest to Koelpura in Motichur forest. A male tiger also had also come there to drink from the same water-hole. The young siblings have grown up – they are 9 years old – and are now advancing through their prime breeding age.

There has been no trace of the male tiger in the western part of RNP after 2004. Further, there are no tigers in the Shivalaks west of RNP. Over the past seven years, there were one or two unconfirmed reports of tiger movement between the eastern part of RNP and the western part of RNP. As a result, all the three tigresses of breeding age are genetically isolated from the rest of the tiger population in Terai-Arc-Landscape. After 2003 no cubs were seen in the western Rajaji National Park.

The three tigresses still range over parts of Kansrau, Motichur, Beribara, and Dholkhand Ranges in the western Rajaji National Park. After the three tigresses die out on completion of their life spans, it will mark the end of the tiger population in the western part of the National Park. The situation suggests that the population of tigers in the western part of RNP is on the verge of extinction; and it also has a tangible threat of shrinkage of the north-western limit of the Indian tiger on the world map.

The time is too short, and a miss will lead us to total wipe-out of tiger population west of the river Ganges. Expert intervention is called for to save the north-western isolated population at the edge of the tiger distribution range in the world. It is for us to revive it with a genetically and numerically viable population of the Indian tiger. The WII-NTCA report of 2011 on the status of tigers, etc., in India recognizes the area extending up to the river Yamuna as a Potential Tiger Habitat (PTH). But such status will be meaningfully utilized on if the potential tiger habitat remains occupied by tigers.

OPTIONS FOR MANAGEMENT INTERVENTION:

Basic Considerations

The western part of the Rajaji National Park where the three tigresses are currently living is reasonably well protected from biotic interference. Human inhabitants were shifted out a few years earlier under a government sponsored Gujjar-Rehabilitaion Program. With the removal of constant biotic stress, the population of sambhar, wild boar, spotted deer, nilgai etc., i.e., the tigers’ prey base has bounced back (the encounter rate is on the rise). But because of low tiger population the occupation of the tiger niche is scant. Leopard, the only other co-predator, is widely distributed in RNP because of the vacant tiger niche. Predation by the leopard is mostly on the spotted deer and the young of the sambhar, nilgai and wild boar. Potential tiger habitat for occupation by tigers west of the Ganges extends nearly 1000 sq km to the river Yamuna. But since the better section of tiger habitat is near the middle part of the western RNP the tigresses have in constant occupation of it.

Proposed Plan of Action

The approach for the restoration of the tiger population in western RNP requires that the three tigresses already present in the area should be taken into account.

Out of the three tigresses, two tigresses are 9 year old, and the third, if it is their mother, should be over 11 years of age. The chances are that two out of the three will secure a mate and breed if the management considers introducing male tigers from the wild gene-pool.

Options:

In order to ensure long-term genetic viability, any program for introduction of new tigers should guard against tigresses getting sired by the same tiger. Even though only tigers can decide which mates to secure, we may consider keeping open the option for using artificial insemination technique, and be in the readiness to do so. For this reason the suggested choice of techniques is:

(a) Introduction of tigers into the area to strengthen wild breeding stock. The WII has the requisite experience gained while their work in the reintroduction of tigers into Sariska and Panna Tiger Reserves; and

(b) It will be prudent to be prepared to use the artificial insemination technique for impregnation of the adult tigresses as a standby for an unpaired tigress, if need arises.

A. Translocation of tigers into the western RNP

1. Protocols: Certain precautionary measures have been considered in charting out a proposed plan of action.

a.       For Import of Tigers of Breeding Age: With three tigresses already in the area occupying two split sections in prime habitat, and not a single male for them, it is suggested to limit the import of tigers into the western RNP at the initiating stage to three – two males and a breeding female. It will help in close monitoring of the tigers. Further imports may be carried out after monitoring the progress of the program and during the following years.

b.      For Identification of tigers for translocation: It is possible to identify suitable individuals only by close monitoring of tiger sub-populations. There will be the need to use a combination of field methods and camera-trap captures so as to minimize error in selection of the tigers to be brought in.

c.       For the Choice of Areas for Selecting Tigers: Lansdowne Forest Division forms the link between Chilla WLS in its west and Corbett NP in its east in the Terai Arch Landscape. These forests accommodate the spill over tigers from eastern Rajaji National Park and the western extension of Corbett National Park. Male transient tigers are often noticed in this area seeking to establish new territories. One of the male tigers may be selected from the Laldhang-Sigaddi forest and the other from Kolhu-chaur-Kalagarh complex to reduce the chances of picking up related tigers. As far as possible male tigers from Chilla WLS (where the population of male tigers is low) or from Corbett tiger reserve (where the high density of tiger populations naturally pushes out the sub-dominants at the fringes of the NP) should not be disturbed. The female breeding tiger needed for this program may be selected from among the tigresses that have no cubs in the tow.

d.      Precautions in Selection of Male Tigers: As a precautionary measure one must not target a male tiger from a well established mosaic of territories established by the males in the source area. Removal of a well established territory holding tiger introduces new intra-specific stresses. The sudden vacation of a prime tiger territory in the land-tenure mosaic impels restructuring of tiger land occupancy pattern. The new occupant of a vacated territory can pose a threat for the young off-spring of the previous male tiger. It is best not to risk such developments by deliberate management intervention. Letting the restructuring of land-tenures happen in tiger populations in a natural way is a part of tiger ecology.

e.       Preferences for the Making the Choice of Male Tigers: A young transient adult is an ideal choice for developing a breeding population. Such tigers are invariably sexually mature sub-dominants approaching physical maturity and looking for spaces to establish themselves. It is also the most adaptive age for any growing tiger. In the absence or non-availability of such a transient tiger an isolated adult or a peripheral young adult male of breeding age may be the next choice.

f.        Preferences for making the Choice of a Female Tiger: The selection of a breeding tigress is ideal if she has bred a litter previously. Breeding tigresses will be, by nature, found settled in a territorial mosaic of female ranges. Both the areas of Choice have a good population of tigresses. Occupation of a vacated range by the neighboring tigress may not be fraught with the type of aggression usually expected in male tigers. Hence, in selection of a breeding tigress there is no restriction on taking one out of a cluster of adjacent established ranges occupied by tigresses.

g.       For Selection of Sites for Release: Kansrao, Motichur, Ranipur, Beribara, Dholkhand forest complex in the western part of Rajaji National Park offer promising sites for the release of the male and female tigers taken from Lansdowne forest. The currently resident twin tigresses range mostly on the northern aspect of the Shivalak Range. The third tigress ranges on the southern aspect of the Shivalak Range in the forest close to Dholkand FRH 6 km away from the pass. There are spaces of unoccupied tiger range between the areas occupied by the three tigresses. The release of the fourth tigress may be carried out in Beribara 2b, in the forest on the southern aspect of the Shivalak Range and north of Beribara FRH.

Under the arrangement visualized above with two tigresses on either side of the Shivalak Range, one of the males may be released in the forest of Paniala 6b of Motichur Range on the northern aspect and the other in the forest of Bam 3, adjacent and to the west of Beribara 2b compartments on the southern aspect of the Shivalak Range.

The sites shown in Fig 1 are suggestive, and may be adapted/ modified according to the situation on the ground at the time of release of the three tigers.

h.       For Time Schedule for the Action in the Field: Introduction of new tigers into the western Rajaji National Park needs to be timed in such a manner as to allow them time to settle down and also stay in proximity of the tigresses; they should not irretrievably drift away from them. If the tigers distance themselves from the tigresses we shall need to take recourse to the second plan of action, i.e., impregnation of the tigresses. Considering that scent marking and mating calls act as anchors for eligible breeding individuals to stay within reach of the calling animals, the months of September-October appear to be suitable for releasing the tigers in the identified release areas in western Rajaji National Park.

B. The Use of Artificial Impregnation Technique for the Revival Program:

This tool will be kept in readiness as a stand-by for use in the months of February after establishing whether any tigress needs to be impregnated having failed in finding a mate.

                     i.      For Source of Tiger Spermatozoa: There may be tiger sperm available with the Centre for Cellular and Molecular Biology (CCMB), Hyderabad, but it is not a choice for this program at all unless they have viable sperm from male tigers of Rajaji-Lansdowne Division in their stock. If the sperm is not available at CCMB bank, breeding male tigers in Chilla and Lansdowne forests will have to be used as the donors for the fertilizing sperm. The choice of virile breeding males can be made from field observations by the WII.

                   ii.      For Collection of Semen from the Free Ranging Tiger(s) For this the involvement of any institution, such as CCMB, IVRI etc., zoo, or even individuals having the requisite expertise and equipment for this work may be involved.

                  iii.      For Timing for impregnation: Tigers have extended breeding season which stretches over almost half the year – from October to March – with peak pairing activity taking place during the three months of December to February. The middle of the month of February is close to the beginning of the decline of the breeding season. However, individuals may vary in their breeding efficiency depending upon their age and breeding condition. Hence, if any tigress has not mated with any male introduced into the area, the month of February should not be allowed to pass unutilized.

For Follow-up Action

Monitoring of tigers using radio-telemetry and field methods will have to be carried out as a follow-up action. The monitoring should be aimed at getting regular feed back on the management intervention, so that the action for extending or changing the approach to suit the developments is detected in time. Even otherwise constant monitoring is needed on tiger behavior and ecology as a reviving population.

Risks:

1. The behavior of the tigers is unpredictable. There may be in-fights among the tigresses for domination and occupancy of prime habitat, and redistribution of their ranges. The suggested plan for release of the introduced tigers has been made with great caution, and, ideally, the males and the females should settle down in healthy breeding relationships. The element of uncertainty in the final shape the pairing cannot be wished away. There is no stopping of one of the males dominating the other and mating with all the tigresses. It is even possible that the males may not mate at all with any of the females. In which case the females may have to be artificially impregnated using the sperm from these two and two other males from Chilla-Lansdowne-Kalagarh population of tigers.
2. The number of tigers being introduced is only three at the initial stage. It is too small for ensuring long-term genetic as well as numerical viability of the population, even if the tigresses breed according to our expectations. The first year is a year of experimentation. Errors may be expected, since we are breaking new path in tiger conservation. Observation and rectification of defects and errors if any discovered in the program must be brought to light and attended to.
3. It is not really predictable which tigresses will contribute to the new generation of tigers in the western Rajaji National Park. In the case of absence of any results during the first year, the focus of attention of breeding males may shift from the older tigresses to younger ones.
4. We do run a risk of weakening of monitoring efforts after first breeding of tigers. The risk will come from human and from equipment failures. Non-availability of replacement of defective, damaged or lost equipment can be perceived as the source of risk to the program from equipment failure. But these sources of risk are not insurmountable.
5. If we miss this opportunity, we shall be guilty of shrinking the tiger distribution range by our decisions. Attempts to re-introduction of tigers after having lost the tigresses may even generate embarrassing situations involving public sentiments. And last but not least, it will be a great blow to tiger conservation in India. It is a Catch-22 situation in which, even with every perceived precaution taken, the chance of failure, how-so-ever remote it may seem, cannot be ruled out.

Financial Support

NTCA and the Uttarakhand Forest Department may consider supporting the program.

EXPECTATIONS FROM THIS PROGRAM

            If all goes according to the plan, one can expect to come across cubs born in the area by June 2013.

The program is expected to help in reviving tiger population in the north-western limit of the range of distribution of the Indian tiger, Panthera tigris tigris, in the world.

Besides saving the tiger in this crucial space, it will also provide new expertise to our tiger conservation skills by developing the protocols for reviving tiger populations in genetically isolated and very low tiger density areas all over in India.

The experience gained will make it possible for us to overcome the handicap of skewed sex ratios and the threat of genetic depression through inbreeding in such isolated small vanishing tiger populations.

This program can break new paths for dealing with the situations where vulnerable and unviable populations, and where numbers range between 3 to 15, may need management interventions.

For the Rajaji National Park the program promises a boost to wildlife tourism in the western part of the National Park. At present Chilla draws maximum visitation from day-tourists, and the western RNP in not as popular. Tiger is undoubtedly the star attraction with the elephant next after it. The program is expected to improve the opportunities to see the tigers in the western part of the National Park. The tourism generated employment opportunities and the wear and tear of the tiger habitat will even out between Chilla and western Rajaji areas.

Therefore, the call of the Rajaji tigresses must not be ignored.

Attachment: Fig 1, Map for illustration.

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* Y.V. Jhala, Q.Qureshi, R. Gopal, and P.R. Sinha (Eds.) (2011). Status of the Tigers, Co-predators, and Prey in India, 2010. National Tiger Conservation Authority, Govt. of India, New Delhi, and Wildlife Institute of India, Dehradun. TR 2011/003 pp-302.

SAVING THE LAST TIGERS IN THE WESTERN RAJAJI NATIONAL PARK

            Rajaji National Park is, at present, the north-western limit of the distribution of the Indian tiger, Panthera tigris tigris, in the world. The latest officially estimated population of tigers, based on statistical modeling approach, in Rajaji National Park (786 sq km) is between 8 and 15*.

Because of the river Ganges, flowing north to south and the blocking of the Chilla-Motichur east-west corridor across the river the tiger population in Rajaji National Park (RNP) is genetically and geographically divided into two parts. The eastern population inhabits the 249 sq km Chilla Wildlife Sanctuary, and has a still active tenuous link with the Kalagarh-Corbett-Haldwani tiger population. Transient tigers help maintain the genetic linkage in this part of the Terai Arc Landscape. But, over the past seven years of my field monitoring of tigers in RNP there is no instance on record of any tiger having crossed over from the eastern part of RNP to the western part of RNP, which consists of the Rajaji and Motichur Wildlife Sanctuaries; or vice-versa. The situation suggests that the population of tigers in the western part of RNP is the ultimate north-western limit of the distribution of tigers in the world.

Out of the estimated figure of tiger population, most of the tigers are in Chilla Wildlife Sanctuary. The 249 sq km Chilla Wildlife Sanctuary, east of the river Ganges, has 8 resident tigers. But in the western part of RNP there are only two resident tigresses, and they are siblings born in the winters of 2002-2003.

I have continuously monitored tigers in RNP since 2001. There were a male and a female tiger in Kansrau-Beribara section, and a male tiger in Dholkhand-Ramgarh section in the western part of Rajaji National Park. These tigers often crossed the Shivalak ridge in their perambulations and were noticed in different forest Ranges at different times. The cubs appeared for the first time out with their mother in Kansrau Range in 2003. The two male tigers and the mother of the two siblings are no more. The two sisters of 2003 are now grown up adults, and are in the prime of their youth. Their home ranges cover parts of forest areas in Kansrau, Motichur, Beribara and occasionally east of Dholkhand Ranges of Rajaji National Park.

The two tigresses are genetically isolated from the population of tigers in Chilla Wildlife Sanctuary. Even though they are of breeding age, there is no male tiger from which tiger conservation program of India can expect a change of continuation of occupancy by tigers of the western part of RNP. In effect, when the two tigresses die on completion of their life spans, it will mark the end of the tiger population in the western part of the National Park, notwithstanding the declaration of the area as a potential tiger habitat.

The situation is evidently and significantly alarming. It is a case of prospective die-out of an isolated small population of the tiger which, with immediate management intervention can be avoided. Potential tiger habitats are of no consequence unless we encourage their occupancy by tigers. Expert intervention is immediately needed to have the north-western end of the tiger distribution in the world occupied by a viable population of tigers. The area is reasonably protected, with good prey base of sambhar, wild boar, spotted deer, nilgai etc., for the tigers. It currently has living tigresses in it. And its suitability is proved by the studies already conducted by the Wildlife Institute of India before declaring it as a potential tiger habitat. The alternatives for immediate action under the present situation can be the introduction of a male tiger (or a combination of male and female tigers) into the area, or, till such time as the first alternative takes place, the two adult tigresses are caught, impregnated by artificial insemination techniques, and radio-tracked for constant monitoring and further studies. The time is too short, and a miss will lead us to total wipe-out of tiger population west of the river Ganges.

Vinod Rishi

22.04.2012

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* Y.V. Jhala, Q.Qureshi, R. Gopal, and P.R. Sinha (Eds.) (2011). Status of the Tigers, Co-predators, and Prey in India, 2010. National Tiger Conservation Authority, Govt. of India, New Delhi, and Wildlife Institute of India, Dehradun. TR 2011/003 pp-302.

A Leopard's Love

Our people think the leopard is a blood-thirsty killer of all life. This is the proof of how little we know about the sentiments of leopards. I have other examples too to prove the point. But this one will suffice as an illustration. The large leopard played with the calf for 45 minutes and the small creature was so unafraid of the predator it even tried to suckle milk from it........... http://www.dailymail.co.uk/news/article-2131060/Leopard-plays-baby-antelope-South-African-bush-happy-ending.html

Does it really justify our people treating all leopards as vermins, and shooting them down on any pretext?

Project Leopard

Uttarakhand Forest Department is considering the launch of a State Level Project for the conservation of leopard. Project Leopard, as it was referred to in the newspaper report, is the need of the day. Poaching, panic reactions, low prey base in the natural habitat of the leopard in the State, scavenging by leopards, attacks on human beings, and the comparatively lower public profile than that of the tiger make it a difficult endeavor to carry out expecting support from the public who thinks all leopards are man-killers.

It is evident that the Project Leopard will have to be designed and implemented very carefully. The newspaper report indicates that appropriate experts have been involved in the development of the Project. I will like the following points to be examined and, if found useful, accommodated for action in the Project:

1. My personal experience over the past five years of my residence in a village at the edge of forest with leopards in it indicates that the leopards avoided being spotted by human beings. People in and around my village had seen a fleeting glimpse of a leopard only on two occasions over the past five years. There was no panic, and it was treated as a normal incident, contrary to the way the effect of the sighting of leopards is reported in the print media. Perhaps the people with urban background are too far removed from nature to understand that mere sighting of a leopard is not an indicator of the presence of a man-eater. Here, Jim Corbett seems to have left a permanent psychological set back on the minds of the people through his hair-raising adventure with the Man-eating Leopard of Rudraprayag. The Project will need to work for the change in the attitude of the people toward the sighting and presence of leopards in the forests near their habitation. How it will be effectively done is a matter for the experts.
2. Post retirement years have kept me working for wildlife conservation. Conflict with wild animals is a burning issue. I have visited and interacted on my own with people from a few leopard affected sites, such as Khankra near Rudryaprayag; Dogadda, Laldhang, Sigaddi, Kanva Ashram, Kimsar and Garahkot in Pauri; in around Rajaji National Park and Corbett National Park; and villages near Doiwala, Jhajhra, IMA, FRI, WII and Asarori at the fringes of Dehradun. A fair idea was given to me by the people, and pointers that had bearing on the behavior of the leopard and other wildlife came from their way of life. These pointers gave reasons why leopards turned into problem animals.
1. One significant issue was that of disposal of waste from their homes. In most of the areas people casually threw their domestic waste matter just across the road from their residences, or at random at the periphery of their villages. Even dead domestic animals and animal waste is thrown about in the same casual manner. Leopards are opportunistic scavengers. The dumped waste attracts small mammals, birds and other animals, free living as well as domestic, (including pigs, dogs, monkeys, poultry birds), which in turn attract leopards who find new scavenging opportunities as well as potential prey in such animals. Project Leopard will have to address to the development of domestic waste disposal approaches so that people correlate their own role in the mitigation of the conflict and conservation of wildlife in Uttarakhand.
2. Forest fires and people who have made sale of firewood as their calling intensify the problem of leopards others face. Fires take place mostly when leopards have cubs accompanying their mothers. Head-loaders bring out firewood all the year round from the forest to meet the enormous and regular demand of bakeries and small roadside dhabas near the cities. These centers of heavy firewood consumption use highly expensive LPG sparingly. The combined effect of fires and the year round cutting of small trees and bushes by the head loaders  is that the forest gets exhausted of its resource-base for the leopards, particularly where the forests  are close to towns and cities, by the time summers set in. The effect of re-grown vegetation in the forest after monsoons is off-set by mid summer by these two factors. The prey base and the shelters under the green cover are drastically reduced at a time when leopards need them  most for raising their families. Fires drive leopards with cubs closer to the human habitation and thinned ground cover makes their sighting frequent. The Project may need to develop strategies to overcome these constantly present hurdles in conservation of leopard habitat.
3. Leopard habitats are changing in their quality and extent inside the forests even with management interventions. No surveys or studies have been done by anyone on the relationship between management practices and wildlife shifts till date on this aspect of leopard ecology; the effect of management practices and unplanned human interventions need to be researched. The Project must establish a research cell for not only leopard habitat and prey base studies but also for studies on their inter-relationships with co-predator like the tiger and co-scavengers like wild pig, dogs, monkeys etc., the dynamics of prey substitution and distribution, and other related issues.
4. Not all leopards are man-killers. Jim Corbett could find only two leopards, the Panar and the Rudraprayag man-eating leopards, during his entire life as a hunter of man-eaters. The leopard and tiger density at that time was many-folds of what we have today. Possession of firearms by the local people was a rarity in those days. The real man-eaters are not easy to deal with. People lived insecure and completely helpless lives in the far-flung isolated hamlets, and fell easy prey for the man-eaters. But too many leopards have been declared man-eaters over the past five years, and also shot. Jim Corbett could eliminate the problem by shooting just two real man-eaters, but we have failed even after killing a larger number of declared man-eaters. Our actions have supported and strengthened the idea in the minds of the people that every leopard is a potential man-eater. Media persons are also people and they also go along with such ideas. Most of the incidents of leopard attacks resulting in injuries to the people have taken place when leopards were surrounded by excited and violent mobs and  their escape route was blocked. People need to know the procedures and techniques to deal with a cornered leopard, whether in or outside a house. The Project will help people and conserve leopards if such issues are brought under its agenda.
5. I am not convinced with the projected figures for the population of leopards in the State. The ground evidences do not support these figures; our methods and models for estimation of leopard populations do not recognize the limitations of the difficult terrain over which the leopards occur, the spatial niches they occupy and the habitat suitability indices for the animal. The methods found useful in plains areas are not effective in the outer and middle Himalayan leopard ranges. The only approach for assessing the actual area and determining the sampling units for leopards in our hills is the down to earth Habitat Occupancy Mapping technique. Even though some knowingly speak about, it is neither understood nor effectively carried out even by the most of the well meaning experts. Project Leopard will have to develop accurate techniques for understanding where and how many leopards are resident in the forests and scrub of the Uttarakhand landscape.

Lest my suggestions are considered assertive and exhaustive I should clarify that I do not believe that the issues involved are unknown to the officers of the forest department, or to the experts on the subject. I have dealt with Project Elephant and Project Tiger, and man-wildlife conflicts. I have shared some of the points I have presented to the Uttarakhand Forest Department for consideration while formulating the Project. 

MAN, MASK AND MANEATER

Introduction

       During a period of six years between 1860 and 1866 A.D., a total of 4,218 people lost their lives due to tiger attacks in the forests of the combined delta of the Ganges- Brahmputra river system. Indiscriminate hunting of the tiger population down to its threshold limit and the decimation of its habitat from about 20,000 sq. km. at the turn of the last century to less than 10,000 sq. km. in the recent years could not put a check on the tiger attacks. The Project Tiger authorities in Sunderban Tiger Reserve identified the control of the man-tiger conflict arising out of the tiger attacks as the key problem in the region. Over the past 14 years they have, through a chain of experimental innovations, succeeded in reducing the average annual toll of human life due to tiger attacks from about 60 in 1973 to less than 30 in the recent years. The ultimate goal is the complete stoppage of the loss of human life while maintaining a viable population of the endangered species in its pristine habitat. As another link in the chain of ongoing experiments for devising suitable methods and means to protect human lives, human face-masks were tried out on the principle of mimicry in nature during 1986-87.

The Hypothesis

       When stalking its intended victim, the tiger takes care to choose the moment of its attack when its quarry is off-guard. Case studies of tiger attacks on human beings in Sunderbans indicated that almost all the attacks were made from behind, the unguarded side of the victims. An alert backward stare may, therefore, reduce the chances of attack by denying the tiger an opportunity to catch its human quarry off-guard. In nature, many organisms use false eye-spots for protection against their enemies. Human face-masks worn on the backside of the head create an illusion of watchfulness on the part of the wearer.

Materials and Methods

      2500 human face masks made of lightweight rubberized plastic material were distributed among the people permitted to work in the buffer zone of the tiger reserve during a period of one year from November 1986 to October 1987. The yearlong experiment was divided into three phases, designed to cover one complete annual cycle of human activity and exposure to conditions under which tiger attacks take place. Phase I covered the activities of fishing and wood cutting in timber coupes between November 1986 and March 1987; Phase II covered mostly the activity of honey collection during the hot months of April and May 1987; and phase III covered the activity of fishing between the months of June 1987 and October 1987.

      In Sunderbans, people live in boats when working in the forest areas. Fishermen confine their movements to estuarine channels and do not enter deep into the forest on foot. The woodcutters work primarily in the timber coupes in large groups and advance into the forest over land at the heads of the clearings made by coupe operations. Only the honey collectors penetrate the mangrove wilderness deep on foot. All parties camp in boats anchored away from the banks of the estuarine channels for fear of tiger attacks. The activity of honey collection places the workers in the most vulnerable situation for tiger attacks. The honey collectors virtually invite tiger attacks by crawling through dense tangle of mangrove vegetation, unarmed and visually separated from one another by thick screens of the under growth, till a honey comb is spotted; all caution is thrown to the winds and unmindful of where they step, their eyes riveted on the honey bee buzzing through the mangrove foliage overhead, they often fail to notice the presence of the tigers, and fall easy victims to their attacks. Whereas Phase I was the introductory phase of the experiment, Phase II subjected it to the severest possible test for its efficacy as a protective device. Phase III was designed to find out the impact of the experiment and its acceptability to the local people.

       During the first phase masks were distributed only to the people who came forward for voluntary participation in the experiment, while in Phase II the use of masks was made compulsory for the honey collectors. The demand for masks was treated as an indicator of the interest of the people in the mask as a useful device in protection of human lives and therefore an indicator of the impact of the experiment on the local people. During Phase III masks were distributed only on demand.

        All cases of tiger attacks were investigated by a team of officers of the Research Wing of the tiger reserve. The technique of investigation included verification of the evidences left behind on the spots of accidents, cross examination of the companions of the victims and sample cross-checks through informal discussions with the survivors of the attacks. The system of awarding compensation to tiger victims ensured reporting of all incidents of tiger attacks on human beings in Sunderban Tiger Reserve.

Results and Discussions

       During Phase I, out of a total of 4,943 people permitted to work in the buffer zone of the tiger reserve, 877 workers – 410 coupe workers and 467 fishermen – volunteered to use the masks after the purpose and the method of use of the masks were explained to them. From among the volunteers, 1 coupe worker and 2 fishermen lost their lives due to tiger attacks; among the rest 5 were attacked by the tigers. None of the persons attacked were wearing masks at the time of attack. The coupe worker and the fishermen had been using the masks when working in the coupe or catching fish respectively i.e.., pursuing the activities for which permits had been taken. The coupe worker was attacked when during a lunch break he had taken off his mask and gone to catch fish for lunch 2 km. away in a nearby creek. The fishermen were attacked when they had taken a break from fishing and, leaving their masks in their boats, stepped into the nearby bank to collect firewood for cooking their meals. None of the mask wearers were attacked by the tigers, and the results obtained during Phase I encouraged the continuation of the experiment into the next phase.

       During phase II 548 honey collectors and 373 fishermen worked in the buffer zone of the tiger reserve. In all 882 masks were issued to the honey collectors who often needed replacements for masks due to their strings getting entangled in the undergrowth as they crawled through the mangrove vegetation in search of honey combs. The fishermen took 137 masks. Seven honey collectors and four fishermen lost their lives due to tiger attacks. None of the victims were wearing masks at the time of attacks. During the first week of April 1987 two honey collectors lost their lives. Stricter enforcement of the use of masks by the honey collectors while working in the forest resulted in total stoppage of tiger attacks during the rest of the honey collection season; during the entire month of May 1987 no honey collector was attacked by the tigers. All the fishermen who lost their lives during Phase II were attacked when collecting firewood in the forest; none of them wore masks at the time of entering the forest.

      During Phase III, 604 fishermen received masks on demand; all of them had also used masks on earlier occasions. There were no casualties among this section of fishermen, whereas 11 fishermen from among those who had not taken masks died between June 1987 and October 1987 due to tiger attacks.

       An unusual phenomenon was observed during Phase II of the experiment. The permits for honey collection in the tiger reserve are issued from Bagna and Sajnekhali stations of Project Tiger only. Unless there is an accident, the permit holders do not surrender their permits before the honey collection season is officially closed down because their earnings depend on the quantum of honey collected by them. The permit holders from both the stations work in the same areas. The permit holders from villages around Bagna are more orthodox and were found to be reluctant to use the masks for the fear of incurring the wrath of their traditional protective forest deities. On the other hand the permit holder from Sajnekhali, who often get influenced by the radical ideas of visitors to Sajnekhali Tourism Complex and forest stations, needed little persuasion to use the masks in the forest. Consequently, not a single life was lost from among the permit holders from Sajnekhali. The permit holders from Bagna suffered all subsequent tiger attacks on honey collectors during this phase.

       The permit holders from Sajnekhali complained of frequent sightings of tigers and reported being followed by tigers for periods ranging from half an hour to eight hours. Although, they were not attacked by the tigers the fear created by the sudden appearance of the tigers presently compelled them to surrender their permits when the honey collection season was at its peak. By 11the May, 1987 all but one of the permits were surrendered by the honey collectors from Sajnekhali; the last one was surrendered on 15 May, a fortnight before the scheduled time for closure of the operation.

      In spite of the heavy casualties suffered by the honey collectors from Bagna, no one complained of similar encounters with tigers, nor did they surrender their permits till the end of the season.

       During informal discussions with the honey collectors, it was revealed that the honey collectors from Sajnekhali were invariably alerted by the tiger itself as it disturbed the undergrowth behind them while following them. None of the Bagna people accompanying the ill-fated tiger victims knew of the presence of the tiger till their companions were attacked. The honey collectors from Sajnekhali also stated that after following them for some time, the tigers invariably came out in the open , sometimes compelling them to return to their boats, and went away after casting a baleful glance at them. No such incident was recalled by the Bagna people. None of the Bagna people held any faith in the utility of mask as a protective device, while a section of people from Sajnekhali felt that masks may be useful in the forest, but the majority of them expressed that the Sunderban Tiger is too clever to be deceived by the masks for long.

Conclusions

        It was the first time ever that the principle of mimicry was tried out in wildlife management for the control of a serious hurdle in making conservation a mass movement. Although it is too early to arrive at an undisputed conclusion regarding the utility or otherwise of the mask, the preliminary results obtained during the yearlong experiment indicate the possibility of developing the mask as a protective device against tiger attacks on human being in Sunderbans. Phase II of the experiment has given important indications that call for replications of the experiment till the hurdles created in pursuit of the experiment because of the traditional beliefs are overcome, and the uninhibited participation by the local people yields concrete results.

Acknowledgements

The author wishes to thank the staff of Sunderban Tiger Reserve in general, and Shri N.R. Mandal and G. Tanti the Research Wing and Shri B.K. Sengupta, Asstt. Field Director of the Reserve, in particular, for following up the various aspects of the experiment all though its yearlong course with truly scientific zeal and ensuring the elimination of personal bias. The author is also grateful to the people of Sunderbans for their participation in the experiment.

MONITORING TIGERS IN THE TWENTY-FIRST CENTURY INDIA

Introduction

The indiscriminate hunting of tigers had greatly reduced their numbers in the country’s forests: from 40,000 at the beginning of the twentieth century, to 4,000 tigers in 1965 (Gee, 1964). The rapid disappearance of tiger populations was noticed first by some hunters, naturalists and foresters (Thapar, 2001). The Divisional Forest Officer of Palamau Division in Bihar carried out the first ever systematic survey in Garu Range of his division in 1934 (Nicholson, 1934). The exercise was repeated in Palamau in 1936 and 1938 (Chaudhuri, 1938). It marked the beginning of the monitoring of tiger populations in India.

Over the next 75 years, 1934 to 2010, the monitoring of tiger populations progressed through three distinct phases of development. The first phase covered the years from 1934 to 1971, and during this phase different field methodologies for counting tigers were tried out in some tiger habitats. Since 1953, monitoring of tiger populations became an annual feature in Kanha. Schaller, during his research study from 1962 to 1964 in a small part of the Park, (Schaller, 1967) identified 11 adult tigers from their facial markings (Panwar, 1979b). S.R. Choudhury developed Co-operation Tiger Census methodolgy in 1972 (Choudhari 1970, 1971, 1972). Mishra applied Stratified Sampling approached to his Track Counts in Palamau for four years (Mishra, 1970, 1971, 1972, 1973).

The next phase, from 1972 to 2004, systematized State and National level monitoring of tiger populations. The first all India tiger census took place in 1972 using ‘Co-operation Tiger Census’ methodology, and the methodology employed by Project Tiger from 1973 to early 1980s (Choudhury, 1970a, 1970b, 1971, 1972a, 1972b, 1979); ‘Pugmark Census Technique’ (Panwar, 1979a), a highly simplified deviant of Co-operation Tiger Census replaced ‘Co-operation Tiger Census’ in mid 1980s and remained in use by Project Tiger till 2004. A new statistical estimation approach using Camera-Trap and Capture-Mark-Recapture model was suggested for monitoring tiger populations (Karanth, 1987, 1988, 1995, 1999, 2003; Karanth et al. 2000, 2002). Refinements in field methodologies were suggested by some (Rishi, 1997, Singh, 1999); analysis of pugmarks using computer software was introduced in West Bengal (Roy, Undated). A group of specialists recommended a judicious mix of both the modified field methods and statistical approaches for use in monitoring tiger populations (Singh, et al, 1997).

The third phase in the development of monitoring techniques started in 2005 by the newly constituted National Tiger Conservation Authority (NTCA). Numerical census of tigers was replaced by Systems Analysis approach using a heirarchical model and statistical estimation techniques for determining the status of tiger populations (Jhala et al. 2005a, 2005b). Other methods using different indices, such as the Pugmark (Digital Image) Analysis technique (Sharma et al, 2001), and the estimation of tiger populations using DNA profiles (Goyal, et al., 2007) are being developed for monitoring tiger populations in India.

The paradigm shift in the approach for monitoring tigers – NTCA’s holistic approach

National Tiger Conservation Authority (NTCA) made a mention of the criticism faced by the pugmark based census methodology and the limitations of the alternative proposal to estimate tiger densities using camera traps as the reason for adopting their new approach.

In this approach NTCA applied a hierarchical model and statistical framework for monitoring tigers and other animals. The entire tiger range in India was converted to 6 Landscape Complexes and used Forest Beats or equivalent areas covering 15-20 sq km of wildlife habitat as the smallest sampling units. The units were categorized in terms of tiger sign abundance classes – high, medium, low and no density class – at Forest Beat sampling unit level and at 100 km2 area resolution level. Population densities for tigers were estimated in 5 – 13 replicates of the size of 100-200 km2 in each of the tiger sign abundance classes. Mark-Recapture sampling method using camera traps was used to find out tiger densities. Extrapolation of densities was carried out at landscape level, followed by conversion of densities/indices into numbers. Computer programs specially designed for the purpose were used for the analysis of the data. (Jhala, Y.V., et al., 2005a, 2005b, 2008).

The results of the holistic approach were declared in 2008. The estimated all India tiger population is reported to be between 1,165 and 1,657, with a mid value of 1,411 tigers in India. For public consumption the mid value is reported as the population of tigers in India. (Jhala, Y.V., et al., 2008).

Reliability of results from current approach for monitoring and conservation of tigers

A. National Level Monitoring:

1) The figure of 1,411 tigers is the arithmetical mid-value of a statistical range with a minimum value of 1,165 and a maximum of 1,657 – a margin of 492 numbers. A large population is in an indeterminate grey area; making the reported status of tigers in India vague.

2) The field data was collected in 2005-2006 over an extended period of time, which does not define a temporal reference point for comparison with later date estimates. Small populations of tigers can disappear in an extended time frame. There was no fixed date(s) common to all places from where the data was collected and the data does not lend itself for comparison with any other data for monitoring the status of tigers in India.

3) The results do not give the structure of tiger populations: the age, sex and breeding status of the tigers; and the methodology is not designed to provide information on juveniles, cubs and transient tigers.

4) The methodology could not generate reliable tiger habitat occupancy maps and other related records.

a. For instance, the map for northern West Bengal shows tiger occupancy in Gorumara National Park that had no record of resident tigers over the past more than five years; and it shows absence of tigers in tiger occupied areas like Mahananda Wildlife Sanctuary and the northern part of Buxa tiger reserve where one was recently photographed.

b. The sampling based statistical estimation of the extent of area under tiger occupation is erroneous for Sunderbans and many other tiger habitats. Therefore, the extrapolation of densities calculated from such erroneous base-line data cannot give accurate information.

B. State Level Monitoring

Estimated Tiger Populations In Some States

STATES                            MIN         MID-VALUE        MAX

BIHAR                              7                        10                   13
CHHATISGARH              23                      26                   28
ORISSA                            37                      45                  53
RAJASTHAN                    30                     32                   35
KERALA                           39                     46                   53
ARUNACHAL                  12                     14                   18
MIZORAM                        4                       6                     8
N. WEST BENGAL           8                       10                  12

*Source: Status of Tigers, Co-predators & Prey in India. NTCA.

At the State level, too, the results do not help in meaningful understanding of tiger populations:

a. The range of values in small populations is too wide to given any meaning to the status of tigers in the State.

b. So long as the local information places the figure for tigers anywhere within the range – arrived at by a more trusted scientific exercise by an authority no less than NTCA – there is no cause for any alarm even if poachers take a few tigers, as long as their presence or activity is not detected. The advantage goes to the poachers.

C. The Information Generated by the Approach

The conservation of tiger in India starts with the knowledge about some basic aspects. It is evident that even 5 years after the collection of field data the exercise failed to provide the crucial information the report was supposed to have given:

a) How Many Tigers? …Not precisely known at national or state levels!

b) Population Trends? …Cannot be known; structure of the populations is not known!

c) Areas where decreasing & why? …Cannot be known; tiger occupancy maps and records are defective!

d) Status of tiger’s wild prey? …Not yet available.

e) State of tiger habitat? …Not yet available.

f) Spacing & connectivity of Wildlife Populations? …Not yet available.

The Question of Monitoring Tigers for Tiger Conservation

The shift from field methods to statistical models made no improvement in the monitoring of tiger populations and habitats. The process has become tardy, time consuming, heavy on manpower, uneconomic, unverifiable, time warped and hence redundant and unsustainable; the choice is: take it or leave it!

(A). Application of Statistical and System Analysis Models

One has to understand that Statistics is a tool and not an end in itself; and that the statistical models create virtual reality. The reliability of the statistical models used in the systems analysis approach depends on what information is being fed to the model designer. A model is nothing more than “…an abstraction of the true experimental situation, representing all relevant features of reality. When used in population estimation, the model will be constructed in such a way that the unknown quantities are expressed in the terms of known or observed quantities” (Overton, 1971). “The first step to successful Systems Analysis is the careful identification of questions to which the model is to be addressed.” (Overton, 1977). But its acceptability depends on the confidence it can generate in the mind of the user – in this case the wildlife manager.

Systems, especially natural systems, are large and hierarchical, i.e., composed of complexes of systems within systems. There is intractability of very large systems for development of differential equations. “Moreover, the system properties emerge not only from their components but also from their linkages. As the systems become larger and more complex, our ability to predict system behaviour becomes less certain.” (Reed, 1995).

It follows that the enormous diversity of the tiger occupied ecosystems in India poses a formidable challenge for application of a hypothetical hierarchical model developed in one or two landscapes to the entire range of diverse ecosystems. Models for Satpura-Maikal landscape cannot be applied to the mangrove forests of Sunderbans or Terai grasslands, or tropical evergreen and semi-evergreen rain forests, or desert and scrub ecosystems.

Modeling is an art. The research work and refinement of Systems Analysis, and statistical sampling approaches is massive in the U.S.A. The adaptation of models developed in other countries does not obviate the need to develop further experience by working in other biogeographically and ecologically different landscapes. At present even the basic research in the Indian tiger habitats is patchy and inadequate for developing models one can confidently apply in India.

(B). Application of Field Methods in Census and Research Work

One of the two field methods, which the field officers had worked with under Project Tiger, used tiger pugmarks as an index for ascertaining individual tiger’s territorial occupancy; and the other, tiger’s identity for estimating tiger populations in a given area. Over the years the distinction between the two has been mislaid and many people think they are one and the same. A controversy was generated in a review of the field censuses in 1987. (Karanth, 1987, 2003; Day, Undated; Banks Undated).

The review of the data from field censuses (Karanth, 1987)

(a). Growth Rates, Density and Biomass of Tiger Populations

Table – 2

Tiger population over the years

Sites                                1972   1979   1984   1989   1993   1995   1997   2001-02

Tiger Reserves                 268       711   1,121  1,327 1,366  1,333  1,498      1,576

Outside Tiger Reserves  1,559    2,304  2,884  3,007  2,384  2,010  2,066

Total                              1,827    3,015  4.005  4,334  3,750  3,508  3,642

Compilation based on the periodic reports of Project Tiger Directorate, Govt. of India.

1. After analyzing the data from the tiger census figures for 1972 and 1984, and using the information from the research work of some wildlife research scholars in and outside India, the review concluded:

i. Between 1972 and 1984, the census figures show phenomenal growth in tiger numbers over the years in almost all parts of the country. Even relatively poor tiger habitats like Bandipur showed high growth rate of 14%, per annum for over 12 years in succession. The research studies in Nepal and Kanha indicate that the growth rates of tiger populations in excess of 6% were abnormal.

ii. The 1984 census data indicated excessive densities and biomass reached by tigers in Indian tiger reserves. The census figures showed that 6 out of 18 tiger reserves, namely, Corbett, Bandhavgarh, Dudhwa, Sunderbans, Kanha, and Ranthambhore tiger reserves, had tiger densities that ranged between 10.89 and 5.79 km2 per tiger, which exceeded the stipulated range.

The tiger biomass in the above mentioned 6 tiger reserves exceeded 10 kg/ km2 whereas a really superior habitat can only support a tiger biomass of 7 to 10kg/km2. Overall, the tiger biomass in ranged between a low of 2.08 kg/ km2 in the Indravathi tiger reserve and a high of 19.58 kg/ km2 in the Corbett tiger reserve.

2. The experimental evaluation of field methods (Karanth, 1987).

With a hypothesis that the pugmark census method was invalid because it depended on the identification of individual tigers from their foot-prints, an experiment was conducted in a zoo to check for its validity: 33 pugmarks tracings were obtained on 2 different substrates from 4 captive tigers, and 6 wildlife managers, who were claimed to have 4 to 12 years of tiger census experience, were asked to give their census figures.

The participants made 72% statistically significant correct choices in distinguishing the pugmark impressions of left and right, front and hind feet, and of male and female tigers. But the participant with 12 years of tiger census experience declined to identify the tigers. The rest of the 5 participants could not identify a single tiger from the pugmarks, and their figures ranged between 6 and 24.

Based on the above, the Review concluded that the field methodology was unreliable. (Karanth, 1987).

Revisiting the Controversy

(1) Basic premises used for the experiment for validity of Field Censuses

Certain premises made in the text of the review were not based on literature research. Some of these erroneous statements in the review related to the field method developed by S. R. Choudhury which was used in the 1972 and 1979 tiger censuses in India:

(a) S.R. Choudhury had argued that every tiger could be individually identified from its pugmarks.

Facts in literature: S. R. Choudhury had cautioned against identifying tigers from their pugmarks. (Choudhury, 1972a). His used Co-operation Census Technique and not the pugmark census technique.

(b) The investigator asserted there was no validation carried out of the field method.

Facts in literature: The literature shows that the Co-operation Census Technique was validated by S.R. CHOUDHURY by carrying out field trials in tiger habitats in Orissa and Uttar Pradesh, and control trials in Delhi Zoo and Nandankanan Biological Park in 1970 and 1971; (Choudhury, 1970b, 1971).

(c) The investigator treated two different methods as one and the same ‘Pugmark Technique’:

Facts in literature: S.R. Choudhury’s Co-operation Tiger Census method (Choudhury, 1970a, 1970b. 1971, 1972a, 1979b) and Pugmark method (Panwar, 1979a) were two different techniques, as reflected from the protocols used for arriving at the estimates for tiger populations:

Co-operation Census Technique estimated the approximate size of tiger population in an area by converting field data to the territorial occupancy of tiger populations (Choudhury, 1970b), while the Pugmark Census technique used tiger pugmarks as the primary index for identifying individual tigers for estimating their populations in an area (Panwar, 1979a). The field data collected and the protocols for analysis of the field data were different in both cases, the only commonality was pugmarks traced by using a tiger tracer developed by Choudhury for his technique.

(2) Errors in the Evaluation of the Census Data of 1972 and 1984

i. Erroneous Bench Mark

a. In the census of 1972 tiger census could not be completed in 4/5th of Sunderbans in West Bengal; the Manas tiger reserve in Assam; the Simlipal tiger reserve in Orissa; and in north-eastern India (Srivastava, 1979).

b. After 1972 areas had been added to some tiger reserves (Panwar, 1979b). The numbers of tigers that happened to get added were not adjusted for calculation of densities and biomass to the earlier figure of 1972 for tiger reserves.

c. The 1984 census neither followed S.R. Choudhury’s method, nor did it have missing tigers in the estimate.

The use of 1972 census figures as a bench mark for calculation of growth rates from the complete census figures of 1984 was unscientific.

ii. Error in application of values of population parameters as a standard for ecologically different tiger habitats:

a. The comparison of densities and biomass using values from limited research carried out in ecologically different tiger conservation units was not scientifically valid because of the systemic differences in different landscapes and bio-geographical zones and biomes in other tiger habitats.

b. Cattle biomass is an indeterminate and significant addition to the prey base of tigers. Contrary to the assertion made in the review, that all cattle-kills are reported in India because compensation is paid for them, the facts are different. The carcasses of cattle killed are often not available to establish the claim for compensation, and quite a good number of kills miss getting recorded in the books.

c. The wide variation in tiger densities and tiger biomass shown in the census results of 1984 in India cannot simply be explained away by supposed difference in protection standards or errors in census methodology, without eliminating the effect of managed inputs in ecological productivity of resources and habitats affecting the growth of tigers.

d. Historical records also do not support the assumed rigor of densities a good habitat can attain. Tiger hunting bags recorded by different hunters, and tiger count by Maharaja of Bundi (Sankhala, 1978) indicate existence of higher tiger densities than those adopted from the research in a few other areas.

iii. Error in the Logic of the Analysis:

There was no logic in leading to a conclusion that census methodology was at fault because 6 out of 18 tiger reserves (33%) exceeded the presumed limits of tiger density and biomass, ignoring the 12 reserves where these were well within the stipulated limits.

(3) Errors in the experiment in the zoo:

i. Flaws in the concept and design of the experiment:

a. The design of the experiment did not simulate either the Co-operation Tiger method or the ‘Pugmark Census’ Technique. Co-operation technique used a network of impression pads to provide a single type of standard surface for tracing pugmarks. The experiment by design presented pugmarks from two non-standard surfaces for testing the participants and made a conclusion about the methodology.

b. The alleged length of experience of the participants was not established. In practice, Project Tiger organized tiger census once in four years at National level and once in two years at State level. Any participant to have acquired experience of 4 to 6 censuses would have had to spend a minimum of 7 to 11 years on postings in tiger conservation units. Similarly, for the experience of 12 years of census experience the said participant would need to spend 23-24 years on such posting(s). Such tenures are not allowed to an officer by the government. The reported length of experience with tiger census was not established beyond doubt. Some of the participants may have had tiger census experience on only one or two occasions!

ii. Flaws in the conduct of the experiment

a. The experiment asked the participants to identify tigers from a single parameter: the tiger pugmark. It offered inadequate data to the participants. The missing parameters were: location from where pugmarks were collected, the average stride and straddle of the tiger, and the placement of the tigers’ pugmarks with respect to the direction of their movement used in field census’ techniques for elimination of duplication in counting tigers.

b. In the experiment a serious anomaly was visible: if 70% of the participants had made statistically significant correct choices in distinguishing the sex and the pugmarks of tigers, but they had completely failed in identification of individual tigers and tiger counts, there was an imperative need to further investigate into the source of anomaly.

c. Scientific research protocol also demanded replication of experiment with different sets of participants since tiger census was being practiced in other States, too. It would have eliminated any chance of the participants having been exposed to a non-standard method.

But no replications of the experiment were carried out – the interpretation of results was made from a single sample survey.

(4) Evaluation of the Conclusion Derived in the Review

With defective bench-mark, lack of simulation of the field methodologies, inherent flaws in the design and conducting of the experiment, and only single sample survey, the only interpretations one can scientifically arrive at are:

     1) That it is difficult to count tigers from only one parameter: pugmarks taken from two soil substrates; and

     2) That the shortfall in the skills exhibited by participants in a single trial cannot be treated as the defect in the methodologies.

Pugmarks are a reliable tiger monitoring index – can be used in estimation of tiger populations and research – Other Views:

a. The Wildlife Institute of India tested the statements made in the follow-up of the Critical Review of Field Censuses by the investigator. These were:

(a) the pugmarks are not unique to individual tigers;

(b) they cannot be used for census, but can be used for estimates;

(c) census is subjective and number game;

(d) the census method is not validated quantitatively on wild tigers;

(e) and the field method is vulnerable to extraneous factors (Karanth, 2003).

b. The findings by the Wildlife Institute of India conclusively disproved all these contentions in 2005 (Sharma et al, 2001, 2005).

(a) Their study established that the pugmarks are unique to individual tigers;

(b) pugmarks can be used for population estimation of tigers;

(c) 63% of the Indian experts were 100% accurate in identifying tigers from their pugmarks;

(d) pugmarks census technique had 100% classification accuracy in DFA & Logistic Regression models using only two variables - Length & Width of pugmarks; and that

(e) the use of protocols can help in avoiding influence of extraneous factors (Sharma et al, 2001, 2005).

c. A tiger pugmark-identity correlation field test was carried out by the scientists of the Smithsonian Tiger Conservation Project in Chitwan tiger habitat in Nepal. It involved identification of tigers from their tracks and verifying their identity from photographs of tigers. The team established the validity of pugmark identification in 1996, and extensively used data from tracks in their research work for over 15 years. (Smith et al, 1999).

d. Historically, if pugmarks could not identify individual tigers and leopards, how is it that Jim Corbett did not overkill tigers and leopards in his pursuit of man-eaters, at a time when for every tiger and leopard in India today there were many times more in his times to choose from?

Monitoring Tigers in the Twenty-First Century

The rejection of field methods for estimating the tiger populations was not based on any scientific experiment. There is science in the field methods, too. The reliability of pugmarks as an index for tiger count was questioned and answered over the past two decades. The statistical estimation approaches have also been tried out. The use of statistical modeling approaches in wildlife conservation also can not be ignored. Both the field methods and statistical models are vulnerable to human bias.

Systems Analysis and Ecological Modeling can become a significant component of wildlife management only if the results are verifiable and useful for the user. The problem lies in the lack of appreciation about when and where to use which approach. Blind promotion or rejection of any approach may have an adverse effect on tiger conservation.

It is not the academic excellence but the field staff that will save the tiger. The need of the day is to enable the field level manpower to monitor tigers with user-friendly methods and techniques. The right way(s) to monitor tiger populations and habitats in the 21st century will be the one(s) that ensure the tiger is benefited from our efforts. A fresh look at both the academic and the field approaches is needed. There is no harm in trying to REINVENT OR REPAIR THE WHEEL IF THE EXISTING ONE DOES NOT WORK.

References

(A list of 51 references given in the unabridged paper.)

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