KOLKATA: The Bangladesh Sunderbans, by virtue of its larger area, has more tigers compared with the Indian side, but the Indian section has a better tiger density. Scientists, after collating findings at the mangrove forests of both countries, have said that the Indian Sunderbans has 4 tigers per 100sq km, almost twice that of the Bangladeshside.
The findings, they said, point to better management in the Indian Sunderbans.
“The Bangladesh Sunderbans has a bigger area and the tiger-occupied habitat, too, is higher on that side, but the density is just 2.17 tigers per 100sq km, almost half of that in the Indian Sunderbans,” said Y V Jhala, senior scientist, Wildlife Institute of India.Interestingly, the tiger-occupied area of the Bangladeshi side is also larger: 4,832sq km, compared with India’s 1,841sq km, according to a recent report on Indo-Bangla tiger estimation.
So, why the lower density on the Bangladeshi side? “The reason is poaching, mainly of prey animals,” Jhala said.
“The encounter rate of human sign and sighting was higher in Bangladesh Sunderbans which is further exacerbated by the usage of river channels for transportation of commercial vehicles,” says the report ‘Status of Tigers in the Sunderbans Landscape of Bangladesh and India’.
Since the tiger-occupied area is higher on the Bangladeshi side, that part of the forest has more tigers despite a lower density. “But I believe the tiger population in the Bangladeshi Sunderbans is much below the actual carrying capacity, while the Indian side has reached carrying capacity,” Jhala added.
The exercise, conducted in the last few years, has recorded the highest tiger density in the Sajnekhali range of the Indian Sunderbans; the lowest was recorded in Bangladesh’s Khulna range.
Both countries have undertaken a camera-trap exercise in 2018 to get a more reliable estimate. The exercise at Basirhat and National Park (east) in the Indian Sunderbans is over, but it’s still on in Bangladesh’s Khulna and Sarankhola ranges. “Unlike previous years, when we had one camera station for every 4sq km, this time, we have one station per 2sq km. So, we have got more pictures this time, but are yet to conduct an analysis. After the monsoon, the same exercise will be carried out in the National Park (west) and Sajnekhali ranges,” said Sunderbans field director NilanjanMullick, who also informed that more than 350 pairs of camera traps are being used.
Mahmudul Hasan, divisional forest officer of the Sunderbans east division in Bangladesh, said they had taken several measures to minimise human disturbance. “We are not allowing ships of Bangladesh Inland Water Transport Authority to ply through sensitive zones of the forest. We have also intensified patrolling and research work on the ground,” he said.
DFO of wildlife management, Modinul Ahsan, said the first-phase camera trap exercise in Bangladesh had been started in March. “We had to first train our staff here and then undertake the exercise. We will take out the cameras in April. We are using 239 pairs of cameras,” he said.