NAGPUR: The tiger population in the country is likely to show a rise of 400, which is an 18-20% hike over the 2014 number of 2,226. Prime Minister Narendra Modi is expected to announce the final figure in New Delhi on Monday, which is Global Tiger Day. People in the know told TOI that it would be in excess of 2600.The PM will also release the All India Tiger Estimation Report-2018. This is the fourth estimation after Project Tiger was reconstituted in 2006. The national estimation is done every four years. In 2006, the tiger count was 1,411 followed by 1,726 in 2010.Karnataka is expected to maintain the top slot with 500 tigers followed by Madhya Pradesh and Uttarakhand. The last estimation showed Karnataka had 406 tigers.Even as Wildlife Institute of India (WII) & National Tiger Conservation Authority (NTCA) officials remained tight-lipped on exact figure, they dropped enough hints to indicate that the “increase is substantial”. “The number was even more than what is going to be announced, but to avoid negative repercussions it has been toned down,” some forest officials told TOI.Union environment minister Prakash Javadekar will also be present along with Modi when the announcement is made at 9.30am. Chief wildlife wardens of all states and tiger reserve field directors too have been invited. The two-day meet will also release management effective evaluation (MEE) reports of all tiger reserves.Explaining the increase in tiger numbers, officials said this time they refined the methodology by reducing the sampling effort from 4sqkm to 2sqkm to get more accuracy.“We have 90% pictures of the estimated tiger numbers. More sampling areas were added in more areas which were not covered earlier. Hence, detection probability also increased,” they said.“In Maharashtra, we estimate an increase in tiger numbers between 230-240,” said officials involved in data collection process. In 2006, there were 103 tigers, followed by 169 in 2010 and 190 in 2014.In the 2014 estimation, there were 66 tigers in Tadoba and Andhari Tiger Reserve core and buffer, but now the number has gone up to 86. “Similarly, Pench Tiger Reserve , which recorded 23 tigers in 2014, has shown 38 tigers. Melghat Tiger Reserve numbers are also expected to rise,” said officials.Tigers are being ‘recorded’ in new places. “Today, there are two tigresses with cubs inside Chandrapur Thermal Power Plant premises. Areas surrounding Pench, Tipeshwar (Yavatmal) and Bor (Wardha) too have become source areas. Tigers have staged a comeback in parks like Navegaon (Gondia-Bhandara) where there were none over a decade ago.”In Brahmapuri near Tadoba, though the tiger number has gone down from 44 in 2017 to 40 this year, the number increased in Central Chanda. Besides, between 2014 and 2018, several tigers have dispersed in search of new territories indicating their occupancy has increased.Critics say the estimation methodology has been “messed up” by placing 1 camera every 4-5 sq km to 2 sq km. “This means double the effort, huge data and more importantly reduction of sampled area due to limited number of cameras. This will cause reduction in even minimum number of tigers and sample size,” they argued.The All India Tiger Assessment 2018 is expected to give more accurate results as this was the first tiger census where volunteers and foresters used a digital app to record their observations. The app, M-STrIPES, is an integrated programme for GPS-aided spatial patrolling and ecological assessment of tiger reserves.Critics, however, felt that the M-STrIPES is still not stable in several reserves. Testings have not been properly done and it is crashing. The ecological monitoring latest version was launched in December last year and estimation was conducted in January giving frontline staff little time to get trained and equipped. Moreover, till date mobile phones have not been supplied in most tiger reserves.“There is definitely data fudging where old photographs of tigers were used for the purpose of the report and a cumulative figure is given as number of tigers actually captured,” they alleged.