The estimation indicated a 30 percent increase in the tiger population over the last census of 2010, with an estimate of 2,226 tigers
This article is an exclusive extract from the author’s forthcoming memoir, Environment Through Finance Eyes.
Today, tigers have indeed become a hugely conservation-dependent species. The major threats to tigers are: poaching that is driven by an illegal international demand for tiger parts and products; depletion of tiger prey caused by illegal bush meat consumption; and habitat loss due to the ever increasing demand for forested lands. To gauge the success of conservation efforts as well as to have a finger on the pulse of tiger population and their ecosystems, the National Tiger Conservation Authority (NTCA) in collaboration with the State Forest Departments, National Conservation NGOs, and the Wildlife Institute of India (WII) conducts a National assessment for the Status of Tigers, Co-predators, Prey and their Habitat every four years.
The methodology used for this assessment was approved by the Tiger Task Force in 2005. The first assessment was done in 2006. It had estimated 1,411 tigers (lower and upper limits being 1,165 and 1,657) and the last country level estimation of 2010 had indicated a figure of 1706 (lower and upper limits being 1,520-1,909 tigers). However, the 2010 assessment also showed a decline in tiger occupied area. This decline in tiger occupancy was recorded in areas outside of tiger reserves, indicating loss of habitat quality and extent – a crucial element essential for maintaining genetic connectivity between individual tiger populations. To address this vital conservation concern, the NTCA in collaboration with the WII had delineated the minimal tiger habitat corridors connecting tiger reserves for implementing landscape scale tiger conservation. All tiger reserves began managing their tiger populations based on a tiger conservation plan (TCP), which addresses specific prescriptions for core, buffer, and corridor habitats.
Also Read: The Full Tiger Series by Sudhansu Mohanty
The NTCA and Project Tiger’s moment of glory came in January 2015. The third round of country level tiger status assessment had been completed in 2014, and the team had put together its findings. Now the estimation indicated a 30 percent increase in the tiger population over the last census of 2010, with an estimate of 2,226 – the lower and upper limits being 1,945 and 2,491 respectively. Looked another way, it suggested that India now was home to around 70% of tiger population amongst the 13 tiger-range countries in the world. India’s long history of conserving the species through Project Tiger had come of age. A thrilled Prakash Javadekar who released the estimation report and wrote out the number – 2,226 – on the white board in front of a packed audience, went on to delightfully say that India now was also prepared to export tigers to any country of the world that was interested in conserving this flagship and charismatic animal in the wild!
Every success brings with it dollops of imaginary skepticism and gobs of jealousy from fellow practitioners or those who archly pretend to be one. The intent often is malicious and sinister to trash and fluff the study, and least to do with questioning data on scientific basis. It was hence no different even in the tiger-land. Soon a nattering group of biologists questioned the reliability of India’s recently released tiger population estimation published in a journal from Oxford. I was surprised when I first heard about it. And I wondered: Was it a case of envy and neglect or lack of visibility or all of the above that seeded this and prompted them to question the assessment? I checked with people who were in the know of things. I wasn’t far off in my surmise. The issue went on for a few months. Eventually, it was the team of two outstanding scientists of the Wildlife Institute of India, Yadvendradev Jhala and Qamar Qureshi, who nailed the lies in an article in the April 2015 issue of Sanctuary Asia. I can do no better than let the duo speak in their words and explain it best.
“The reliability of India’s recent tiger population estimation has been questioned by a paper published in a scientific journal by authors from Oxford.
Since 2005, a group of biologists led by Dr. Ullas Karanth have been critical of India’s tiger status assessments. The paper published by his student from Oxford is a reiteration and synthesis of these views. Essentially, the paper criticises the very basis of sound ecological relationships using theoretical statistical models that are based on reducing the quantum of sign intensity of tigers to mere presence or absence. The paper and subsequent press releases consider the use of double sampling in estimating tiger numbers as flawed. The paper further states that the logic of presuming that there should be more tigers in areas where we find more tiger signs is not reliable, though we have demonstrated such relationships with data repeatedly.”
Also Read Part-I: e-Eye Of The Tiger
Then they explain step by step, how the tiger estimation is carried out across the country; the scientific and the pragmatic rationale and the processes involved; the other option of camera trapping all areas for greater accuracy that’s financially costly and in pockets of low tiger numbers even unreliable, compared to the present scat-based DNA analysis.
“We first establish relationships of tiger abundance with tiger habitat extent and quality, prey abundance, human pressures and intensity of tiger signs from areas where we have very reliable information on tiger density through camera traps. We subsequently use this relationship to predict tiger abundance in areas where camera traps cannot be deployed, but are known to have tigers. The Oxford paper in the Journal Methods in Ecology and Evolution and press releases offer few alternatives to our approach at estimating tiger abundance at the landscape scale. The paper talks about using joint distribution modelling of covariates, without realising that this approach too is a form of double sampling – the same principle used by us and ingrained in ecological and statistical theory. Often ‘occupancy analysis’ is considered as an alternative to population estimation.
Occupancy provides estimates of where tigers are found, or more importantly, are likely to be found. We estimate tiger occupancy as a probability of a forest patch to harbour tigers. But occupancy does not tell us anything about how many tigers there are – just that tigers are likely present. Clearly, occupancy is not a solution to estimating tiger numbers.
Also Read Part-III: Tigers’ Wellness Is Our Wellness Too
All this understandably ends up confusing the public and even decision-makers. Differences of opinion are essential and can be positive to conservation. But as we see it, the only theoretical alternative that might serve the purpose even better than what we have been able to achieve for the latest tiger status assessment would be to camera trap all areas where tigers occur. This would unquestionably provide a more precise estimate, but the resources required would be too large, and in some areas that have very low tiger numbers, camera trapping itself would prove to be an unreliable data gathering tool, when compared, for instance, to scat-based DNA analysis. There is the additional problem of stolen cameras (and consequent data loss) that virtually every field biologist has come to terms with when working in human-dominated areas.
The bottom line, in our view, is that this approach may be ideal, but it is impractical. Until scientists are able to camera trap all tiger occupied areas, we cannot currently see a better option to our approach, which uses the best available science and technology to provide reliable estimates of tiger numbers in India. It should be noted that 77 percent of our estimated mid-point of 2,226 tigers came from camera trap data (1,570 individual tigers photo-captured). The remaining 23 per cent were estimated from faecal DNA, plus models based on sound ecological relationships. The actual number of tigers in India are anywhere between 1,945 and 2,491, signifying a major conservation success story.”
Also Read Part-IV: Environment vs. Development: Who Wins?
Succinctly put, Jhala and Qureshi stopped short of calling it a glaring instance of intellectual dishonesty, but to the discerning it was nothing but just that. I’m fairly confident that the duo will soon enough irrevocably nail the lies peddled in a scientific journal to discredit the national tiger survey results as inaccurate and muddling the readers mind. I guess tigers in the wild not only evoke lots of thrill but also oodles of jealousy and heartburns for the also-rans, and consequentially plenitude of shenanigans. I call these aberrations the tiger politics in India where, like any areas of high visibility, the two-legged creatures who fall by the wayside outshone by others on merit and hard yards put in, bristle in green envy and take periodic shambolic potshots at others who strictly follow the ethics of scientific methodology and NTCA’s protocol for tiger population estimation and tiger conservation management. And if I may add in a lighter vein, notwithstanding the fact that despite their leonine persona, the tigers exhibit “secular” values, and are “democratic” in their outlook and behaviour – something truly admirable in today’s fraught times of polarised outlook!
[… to be concluded on Sunday, Nov 26th]
(Reproduced from Indus Dictum, 19.11.2017)