- Recent surveys of big cats and prey in the Sundarbans indicate that numbers for both have increased significantly in recent years, thanks to different conservation measures taken by the Bangladesh government.
- According to the last survey conducted in 2018, there were 114 tigers in the Bangladesh portion of the Sundarbans, while the number counted in 2004 was 440.
- An ongoing camera trapping tiger census has found more presence of tigers across the forest than in earlier counts. The final count of the tiger population will be announced on International Tiger Day, July 29, 2024.
- Experts say that an increase in tigers’ prey animals will reduce human-tiger conflict and help increase the tiger population.
In a heartening turn of events, the world’s largest mangrove forest, the Sundarbans, which spans the southwest border of Bangladesh, is seeing promising signs of recovery for the iconic Bengal tiger (Panthera tigris tigris). Five years ago, the conservation community was deeply concerned about the species’ plummeting numbers in this unique habitat.
This concern was particularly stark when considering the success stories of India and Nepal, where their close tiger cousins had managed to thrive and increase their populations. The decline in Bengal tigers in the Sundarbans cast a shadow of uncertainty over their future. However, a series of dedicated efforts spearheaded by the Bangladesh government and various stakeholders have yielded encouraging results, rekindling hope for the survival and growth of these magnificent creatures.
The key strategies employed in this concerted conservation campaign have centered around preserving the tigers’ natural habitat, tackling food scarcity issues and combating poaching through a collaborative community-based approach. These initiatives have not only benefited the tigers but also the entire ecosystem of the Sundarbans.
Recent surveys conducted jointly by the government’s forest division, German Cooperation and the Swiss unit of the International Union for Conservation of Nature (IUCN) have unveiled two critical findings that paint an optimistic picture of Bengal tiger resurgence.
Firstly, the surveys have observed an encouraging increase in the population of prey animals such as spotted deer, wild boars and monkeys within the Sundarbans. This bountiful prey availability signals a positive turn for the tigers, ensuring they have a steady food supply to sustain themselves and their potential offspring.
Secondly, due to effective habitat preservation measures, the surveys suggest that the forest may now be accommodating a higher number of tigers. This resurgence not only holds promise for the Bengal tigers’ survival but also contributes to the biodiversity and ecological balance of the Sundarbans.
Bountiful availability of prey animals
One of the surveys, a comprehensive three-year census, underscores the importance of six key prey animals for Bengal tigers. Although the number of barking deer has dwindled, the populations of three out of the remaining five prey species have experienced noteworthy growth over the past three decades. Spotted deer and wild boars have doubled in number, and monkey populations have also flourished. Experts highlight that these prey animals are not only crucial for the tigers’ survival but also integral to maintaining the vibrant biodiversity of the Sundarbans.
The survey, titled “Status of Tiger Prey Species in the Sundarbans of Bangladesh,” found that the number of spotted deer, which contributed 79% of the tiger’s food consumption, was 1,41,357; the population had been around 80,000-85,000 when the last census was conducted in the 1980s.
The other favorite prey for tigers in the Sundarbans is the wild boar. This prey animal, which contributes around 11% of the tiger’s food consumption, saw a rise of 45,110 in the latest census. In the previous census, it was some 28,000.
“The previous studies on prey animals of the tiger were very limited. That’s why it was unknown to the scientists what is the status of the tiger’s prey animals in the forest. From the result of the census, we can take the necessary steps for the conservation of tiger food, as this will help to reduce human-tiger conflict. If there is no food scarcity, the population of tigers will increase too,” M.A. Aziz, professor in the Department of Zoology at Jahangirnagar University and a researcher involved in the study, told Mongabay.
He, however, stressed keeping prey animals protected from poachers.
Tiger images were recorded in new places
Apart from prey animals, another promising initiative, a four-month camera trapping study spanning 2,600 kilometers (1,615 miles) in the western zone of the forest, has added to the growing optimism.
The forest department is conducting a census of the tiger population in the Sundarbans. A total of 1,330 cameras at 665 spots were installed to count tigers, deer and pigs in the mangrove forest.
As of now, the analysis indicates that at least 53% of the installed cameras found the movement of tigers, which has created hope and positive expectations about the increased numbers.
“We are now analyzing the images. As every tiger has unique stripes, unique tigers will be identified through their stripes. But the good news is that we got images of tigers in the places where we did not get any image in the previous two censuses,” said Abu Naser Mohsin Hossain, Sundarban West Forest Division officer.
Forest officials said the survey will be completed in April, and the number of tigers will be announced on July 29, 2024, International Tiger Day.
Mohsin said the number of tigers may rise, as the government took various steps over the years to protect the big cats.
Increasing the extent of protected areas is one of them. The government declared 52% of the total Sundarbans (6,017 square kilometers or 2,323 square miles) as protected areas in 2020, while it had been only 23% earlier.
“As the protected area was increased, tigers remained undisturbed and this ensured a good environment for tiger breeding,” Mohsin said, adding that it was possible only because the forest is now pirate-free.
Additionally, to protect the tigers, the government has focused on mitigating tiger-human conflict, which is currently giving dividends.
There are 340 members under 49 village tiger response teams whose task is to protect any tiger any tiger that enters a locality.
“In the last 20 years, 52 tigers were killed or died naturally. But in the last five years, there was not a single incident of human-tiger conflict in the Sundarbans,” Mohsin said.
Sundarbans tiger surveys at a glance
According to the last survey conducted in 2018, there were 114 tigers in the Sundarbans in Bangladesh.
According to the Tiger Census 2015, the tiger population was only 106 in the Bangladesh part of the Sundarbans, down from 440 in 2004.
In 1975, German biologist Hubert Hendrichs worked on “man-eating” tiger field surveys. From his tiger field surveys then, he estimated the number of tigers in Bangladesh’s Sundarbans was 350.
In 1982, Margaret Salter carried out a sample and field survey and estimated that the number of tigers was 425.
Rex Gittins conducted a survey in 1984 covering a 110 km2 (42 mi2) area of the Sundarbans South Wildlife Sanctuary and found the tiger population to be 430-50.
In 1992, the forest department collected data from the people working in the Sundarbans area and estimated the number to be 359.
The following year, Dhan Bahadur Tamang conducted a pugmark census (using tiger footprints to estimate population numbers) covering 350 km2 (135 mi2) of the Sundarbans area and put the number at 362.
Bangladesh has taken several steps for tiger conservation, including the Tiger Action Plan 2009-2017, Bangladesh Tiger Action Plan 2018-2027, the National Tiger Recovery Program and the Wildlife (Conservation and Security) Act, 2012.
In 2010, the International Tiger Conservation Forum held a summit in Russia in which tiger range countries committed to double the global tiger population by 2022; Bangladesh was among the 13 countries. The countries at the summit decided to conduct surveys every four years.
Banner image: A sub-adult Bengal tiger on the river bank in Sundarban Tiger Reserve in India. Image by Soumyajit Nandy via Wikimedia Commons (CC BY-SA 4.0).
Bangladesh tries fences to tackle growing human-tiger conflict in Sundarbans