Here is the first part of an article published by Shri Vinod Rishi in
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 information on the population of tigers in India during the early
part of the Twentieth Century was mostly arrived at from educated impressions and not actual estimation of tiger populations. The rapid disappearance of tiger populations was noticed first by some hunters, naturalists and foresters (Thapar, 2001), and sporadic
attempts were made by some of them to check on the tiger situation in their own backyards. The Divisional Forest Officer of Palamau Division in Bihar carried out a water-hole count of tigers, the first ever systematic survey in Garu Range of his division in
1934 (Nicholson, 1934). He entertained the idea of regular checking of tiger populations, and 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. In 1940s, the Maharaja of Bundi in Rajasthan estimated tiger population in his area (Sankhala, 1969, 1978). 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, estimated a tiger population between 10 to 15 in his study area (Schaller, 1967). He identified 11 adult tigers from their facial markings (Panwar, 1979b). S.R. Choudhury experimented with tiger census in Orissa
in 1966, and subsequently at other places to develop a methodology that came to be known as Co-operation Tiger Census and was later used by Project Tiger. Mishra applied Stratified Sampling approached to his Winter Track Counts in Palamau for four years (Mishra,
1970, 1971, 1972, 1973); Uttar Pradesh recorded 481 tigers in 1969 (Singh, 1969).
The next phase, from 1972 to 2004, systematized integrated 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 for numerical estimation
of tiger populations was 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. The validity of field census techniques was challenged in late 1980s, and 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, with the application of a ‘Holistic Approach’ for monitoring tigers, co-predators and prey species and their habitats, 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). In 2008, the all India Report on the
Status of Tiger, Co-predators and Prey Species was published by the NTCA (Jhala, et al, 2008). The NTCA reported their estimate of the tiger population in India to be between 1,167 and 1,657.
There are 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) being developed for monitoring tiger populations
-to be continued