The frequency of tiger cub sightings by tourists in the Sunderbans has gone up, said foresters.

Their internal surveys, too, point to a similar trend. The increased sightings suggest the apex predator and the ecosystem it lords over both are healthy.

Seeing a tiger in the Sunderbans is more precious than a similar experience in any other forest. This is primarily because the harsh terrain of the world’s largest mangrove tiger habitat makes it inaccessible on foot for tourists.

The only way to tour the Sunderbans is on tourist boats. Each boat is usually manned by an “eco-guide”, who is linked to a Joint Forest Management Committee.

Every time a tiger is seen from a tourist boat, the sighting is registered with the forest department by the guide.

“On October 10, a mother and a cub were seen in Sajnekhali. In the first week of October, two separate cubs were seen without the mother. The two spots are around 5km apart. Last year, in October, a mother and two cubs were seen from another boat,” said an official of the Sundarban Tiger Reserve.

There is a flurry of posts on social media about cub sightings.

“Sundarban, there is nothing like you,” says a post on October 6 last year. It is accompanied with pictures of “a tiger mother with two cubs from the mysterious mangroves”.

Another, made on Saturday, shows another cub rising from the water. “The rise of the future king,” says the caption.

Justin Jones, deputy field director, Sundarban Tiger Reserve, linked more cub sightings to a rise in the tiger population.

“The tiger-sighting frequency used to be very low in the Sunderbans in comparison to any other tiger reserve. The cub-sighting frequency was even lower. But that is increasing because of a rise in the tiger population.

“In the Sunderbans, the tigers breed between late November and end-January. The movement of tigers peaks in the run-up to the mating season. Males move across territories in search of partners. Females move within their territories. October is the time when the maximum number of sightings happen,” said Jones.

The last quadrennial national tiger census had its report — Status of Tigers: Co-Predators and Prey in India, 2022 — published in 2023. Prepared by the National Tiger Conservation Authority (NTCA) and the Wildlife Institute of India (WII), the report estimated 101 tigers in the Sunderbans. The number was 88 in the 2018 count.

The report estimated that the tiger density in the Indian part of the Sunderbans had reached 4.27 per 100sq km. The mangrove forest’s estimated carrying capacity is 4.68 tigers per 100sq km, the report said.

More than one expert has said the tiger count in the Sunderbans is nearing its saturation point.

Rajendra Jakhar, the field director of STR, said it is a “premature” assumption.

“How much a particular habitat can take in can be found out as the number grows. It is not an exact science, like mathematics. With reduction in human interference and a rise in the prey base, the carrying capacity of a habitat goes up. It can accommodate more. It is unfair to put a number and say this is the limit,” he said.

“Because of the harsh terrain, large areas of the Sunderbans are free of human habitation. Our policies and protection measures have also helped in reduction of human interference. The tiger population is healthy and growing,” he said.

The frequency of the sightings of deer fawns has also gone up in the Sunderbans. “There is a stable prey base of deer, wild boar and other animals,” Jakhar said.

Besides the quadrennial national census, the state forest department conducts an annual tiger count. As part of that study, trap cameras were placed in the forests of the Sundarban Tiger Reserve and Sundarban Biosphere Reserve (SBR), which covers the forests of the South 24-Parganas forest division.

The cameras were in place from late November 2023 to early January 2024.

“We had around 20 photographs of tiger mothers with one or more cubs, the highest in recent years,” said a source in the forest department.

Twenty pictures do not mean at least 20 cubs. One cub may have been captured multiple times.

Shiladitya Chaudhury, wildlife enthusiast and photographer who has been visiting the Sunderbans for almost three decades now, acknowledged that the frequency of cub sightings has gone up.

“It is a very healthy sign. It shows that the tiger is thriving in the Sunderbans,” he said.

Chaudhury also said that the nature of tourism in the Sunderbans has evolved.

“Earlier, there was hardly any organised tourism. Fishermen and other residents would take tourists out on a boat. That has changed. Now, there is an organised tourism sector in the Sunderbans. The guides have been well-trained by the forest department. They know the islands where the probability to see a tiger is more than other islands. The tigers are also gradually growing used to tourist boats,” he said.