KOLKATA: The Indian Sundarbans has registered a rise of at least 14% in its tiger population, recording the presence of a minimum of 100 big cats – from 88 in 2019 – in the all-India tiger estimation report released by Prime Minister Narendra Modi in Mysuru on Sunday.
Foresters said the “at least 100” figure was based on evidence of that many unique individuals clicked by camera-traps; the actual number may be higher. In the 2019 report, 85 unique individual big cats were clicked in the Indian Sundarbans. Based on that figure, it is a rise of over 17%.
The 88 figure of 2019 was the average of the lower count (85) and higher count (90) of that year. This year, however, no lower or upper limit has been provided, in a deviation from the usual practice since 2006.
The minimum tiger population estimation in India has been pegged at 3,167. This means the Indian Sundarbans has at least about 3.2% of the country’s total big cat count. Of the five tiger landscapes in India, three – Shivalik Hills & Gangetic Plains, the Sundarbans and the Central Indian Highlands-Eastern Ghats – have registered a growth in population estimation over the data released four years ago.
Whereas scientists had sounded the alarm during the release of the report in 2019, saying the land of the mangroves had almost reached carrying capacity, foresters here believe the tiger population rose mainly on the back of a solid prey base.
Sundarban Tiger Reserve (STR) field director Ajoy Das said the reserve forest had also secured a “very good” ranking, with a more than 76% score in the ‘Management Effectiveness Evaluation of Tig-er Reserves in India’ report.
‘Sundarbans spurt due to good prey base’
Kolkata: Tigers aged more than one year had been taken into account for the exercise.
Sundarban Tiger Reserve (STR) deputy field director Justine Jones said a prey-base estimation recently carried out in the Indian Sundarbans had pegged the density of spotted deer – the tiger’s main prey – between 0.8 and 1.4 per square kilometre. “The density of wild boar is a little higher,” Jones added. “Though in terms of habitat management we can do very little in the Sundarbans, in terms of protection measures, we have taken a lot of steps in the last few years, which resulted in a healthy prey population and hence, the resultant increase in tiger numbers,” he said.
A total of 788 pairs of camera-traps were used during the exercise, conducted between December 2021 and February 2022. While the traps were used to get an idea of tiger numbers, for the prey-abundance exercise, the department had gone paperless. Two apps – polygon search and patrol app – were used to record data on sign survey that gave a better estimation of prey, said a forester.
Sunday’s report said though the Sundarbans tigers were well-suited to the mangrove ecosystem, their habitat was confined. “The tiger population and landscape are both threatened by biotic interference in the form of forest exploration, fishing, palm and timber extraction, and the expansion of waterways. To preserve the ecological integrity of the area, cross-border collaboration and knowledge exchange between India and Bangladesh are imperative,” it said.
State wildlife advisory board member Biswajit Roy Chowdhury said sighting of both sub-adults and cubs had increased in the tiger reserve area in recent years. “So, we were expecting a rise in numbers this year,” he added. According to another member of the board, Joydip Kundu, credit for the good show should go to field staff. “The focus should be on strengthening protection measures,” he said.
Foresters said the “at least 100” figure was based on evidence of that many unique individuals clicked by camera-traps; the actual number may be higher. In the 2019 report, 85 unique individual big cats were clicked in the Indian Sundarbans. Based on that figure, it is a rise of over 17%.
The 88 figure of 2019 was the average of the lower count (85) and higher count (90) of that year. This year, however, no lower or upper limit has been provided, in a deviation from the usual practice since 2006.
The minimum tiger population estimation in India has been pegged at 3,167. This means the Indian Sundarbans has at least about 3.2% of the country’s total big cat count. Of the five tiger landscapes in India, three – Shivalik Hills & Gangetic Plains, the Sundarbans and the Central Indian Highlands-Eastern Ghats – have registered a growth in population estimation over the data released four years ago.
Whereas scientists had sounded the alarm during the release of the report in 2019, saying the land of the mangroves had almost reached carrying capacity, foresters here believe the tiger population rose mainly on the back of a solid prey base.
Sundarban Tiger Reserve (STR) field director Ajoy Das said the reserve forest had also secured a “very good” ranking, with a more than 76% score in the ‘Management Effectiveness Evaluation of Tig-er Reserves in India’ report.
‘Sundarbans spurt due to good prey base’
Kolkata: Tigers aged more than one year had been taken into account for the exercise.
Sundarban Tiger Reserve (STR) deputy field director Justine Jones said a prey-base estimation recently carried out in the Indian Sundarbans had pegged the density of spotted deer – the tiger’s main prey – between 0.8 and 1.4 per square kilometre. “The density of wild boar is a little higher,” Jones added. “Though in terms of habitat management we can do very little in the Sundarbans, in terms of protection measures, we have taken a lot of steps in the last few years, which resulted in a healthy prey population and hence, the resultant increase in tiger numbers,” he said.
A total of 788 pairs of camera-traps were used during the exercise, conducted between December 2021 and February 2022. While the traps were used to get an idea of tiger numbers, for the prey-abundance exercise, the department had gone paperless. Two apps – polygon search and patrol app – were used to record data on sign survey that gave a better estimation of prey, said a forester.
Sunday’s report said though the Sundarbans tigers were well-suited to the mangrove ecosystem, their habitat was confined. “The tiger population and landscape are both threatened by biotic interference in the form of forest exploration, fishing, palm and timber extraction, and the expansion of waterways. To preserve the ecological integrity of the area, cross-border collaboration and knowledge exchange between India and Bangladesh are imperative,” it said.
State wildlife advisory board member Biswajit Roy Chowdhury said sighting of both sub-adults and cubs had increased in the tiger reserve area in recent years. “So, we were expecting a rise in numbers this year,” he added. According to another member of the board, Joydip Kundu, credit for the good show should go to field staff. “The focus should be on strengthening protection measures,” he said.
