Sundarbans: Last Mangrove Habitat of the Royal Bengal Tiger

in Article
Published on: 04 October 2018

Sunit Kr. Das

Sunit Kr Das is with WWF and has worked in the Sundarbans as well as Assam. Human-wildlife interaction is his prime area of research. He is also passionate about wildlife photography.

 

Sundarbans is the last mangrove habitat on earth with bagh or the Royal Bengal tiger. Tigers have been roaming its surface since much before human settlement. This place is not only a composition of mangrove and tidal mudflats, twisting rivers and creeks, but is also a mystifying panorama of millions of trees creating a dense, green canopy. Spread over 10,000 sq km including Bangladesh and West Bengal of India (Das et al. 2012), the habitat is more than a woody endeavour as it represents the emotions of the citizens of both the nations. It is an estuarine phase of the Ganges as well as the Brahmaputra river system forming the largest delta in the world. The littoral forest tree species of these cluster of islands adapted to the peculiar estuarine condition of high salinity, lack of soil erosion and daily inundation of high tides. The forms of life on planet earth are interconnected and in the Sundarbans ecosystem, life is continuously adjusting to new environmental conditions. Therefore, daily struggle for survival goes on between nature and each individual living here.

 

Literally, Sundarban means ‘beautiful jungle’ or ‘beautiful forest’ in Bengali. It is believed that the name was derived from the sundari trees (Heritieralittoralis) that populate this area. From the hoary past to the present, throughout the history Sundarbans has been mentioned in various documents and in various forms. The Indian part of Sundarbans was declared as Sundarbans Biosphere Reserve in the year 1989 under United Nations Educational Scientific and Cultural Organization (UNESCO) Man and Biosphere Reserve (MAB) programme. A biosphere reserve is a protected area that, as George Wright Society defines it, has three objectives: ‘conservation of genetic resources, species, and ecosystems; scientific research and monitoring; and promoting sustainable development in communities of the surrounding region’ (2008). The three agendas have equal significance in a biosphere reserve. National parks on the other hand are meant for conservation mainly; research and sustainable development is only the derived agenda.

 

Sundarbans National Park in India was declared a World Heritage Site by UNESCO in 1997 and as a national park earlier, in the year 1984 by the central government. For common people, Sundarbans is not only a mangrove forest but a symbol of reverence and awe. Religious faiths, myths, and cultural assimilation are interesting aspects of Sundarbans, as well as the fact that it is a perennial source of livelihood for the forest-fringe villagers.

 

The tidal helophytic mangrove forest of Sundarbans experiences tides twice a day. The changing level of water regulates the biological diversity and lifeline for the whole eco-system. The entire forest of Sundarbans is classified under the category of littoral and swamp forest (Champion and Seth 1935). Near the creeks, the forest is mainly dominated by plants like bine (Avicennia marina), tora (Aegialitisrotundifolia) and goran (Ceriopsdecandra). In comparatively elevated areas the vegetation is replaced by species like hetal (Phoenix paludosa) and gewa (Excoecariaagallocha).

 

The distinctive feature of this mangrove is not only its dense forest but its identity as the last and largest mangrove on earth with the presence of the Royal Bengal tiger (Pantheratigristigris). In addition to tigers, sightings of small herds of spotted deer (Axis axis) and wild pig (Sus scrofa) are also very common in the forest giving immense pleasure to onlookers. Other principal varieties of mammalian fauna in this area are leopard cat (Prionailurusbengalensis), fishing cat (Prionailurusviverrinus), jungle cat (Felischaus) and rhesus macaque (Macacamulatta). Among reptiles, it is a common place for endangered species like saltwater crocodile, water monitor lizard, and king cobra along with other varieties of serpents.

 

Sundarbans also supports more than 234 species of residential and migratory birds including some of the globally threatened species. But, over the last 100 years or so due to habitat degradation, anthropogenic pressure and ecological changes, the faunal diversity of Sundarbans has undergone modification. Species like Javan rhinoceros (Rhinoceros sondaicus), wild buffalo (Bubalusarnee), and swamp deer (Rucervusduvaucelii) became extinct during the last two centuries. There was a time when barking deer (Muntiacusmuntjak) was common in the entire Sundarbans landscape, now it is only found in the Bangladesh part of the Sundarbans. Though Sundarbans provides shelter to numerous species, tigers, the rulers of the forests, are the centre of attraction. To see a tiger cross a large creek or river is extraordinary and finding pugmarks on mudflats is always exciting.

 

A century ago, more than 1,00,000 tigers were found in different forests of Asia, and Sundarbans itself—spread across India and Bangladesh—claimed the presence of around 700 tigers. But today, only around 3,200 are left in the wild (WWF TAI 2016:25) including the population of the six remaining subspecies of tigers (Bengal, Indochinese, Malayan, Siberian, South China, and Sumatran) (WWF 2017), and half of the total world population is found in India. The drastic decline of global tiger numbers also had its effect on its Sundarbans population. But no one has a definite answer about the reason for this decline.

 

In Sundarbans' complex ecosystem with dense forest, semi-terrestrial environment along with periodic tidal inundations and the elusive nature of wildlife, it is a tricky task to carry out a study on tigers. Attempts have been made by different organisations to know about the elusive tigers in the mangroves of Sundarbans. Studies on Royal Bengal tiger in the Indian Sundarbans date back to 1972. Divisional Forest Officer (DFO) of undivided 24 Parganas Forest Division, A.B. Chaudhuri, carried out ecological studies and estimated 112 tigers in Sundarban. Later in 1973, the Sundarban Tiger Reserve was formed with an area of 2585.10 sq km and efforts were made by the forest department to estimate tiger numbers based on pugmark method, attacks on humans, and interviews with local communities. However, finally it was revealed that the estimate based on pugmarks is always prone to human error and runs the risk of overestimation.

 

It is also believed that Sundarbans is the most difficult area with the danger of supposedly most aggressive tigers in the world. In 1995, while conducting the census survey based on pugmark method one of the forest department staff fell prey to a tiger. The failure was apparent and made way for the use of remote cameras in the wild, considered more effective and reliable. Remote cameras do not only provide information about the status of a species, but also help find answers to various other questions regarding ecology. For an animal like a tiger with natural markings on body coat, the camera trapping method is very useful and is a revolutionary step in the field of conservation.

 

To demystify the mangrove tigers, for the first time in 2000, remote cameras were deployed in the Indian Sundarbans. But the scenario of camera trapping in Sundarbans is not like it is in other parts of the globe, where it has already been completed with success. The pioneering study based on camera trapping by conservationists were not able to give any convincing result about tigers—the study had limitations as camera traps were set up around fresh water ponds due to lack of forest trail in thick mangrove vegetation (Karanth and Nichols 2000). In Sundarbans periodic tidal phases are the biggest threat for camera trapping as high tides always create the risk of inundation of camera-trap equipment. Rough weather conditions are also an issue to address before starting similar investigations.

 

In 2008, the Status of Tigers, Co-Predators and Prey in India report (National Tiger Conservation Authority [NTCA] and Wildlife Institute of India [WII] 2008) was unsuccessful in coming up with a methodology to conduct the count of tiger due to difficult terrain of the mangrove forest. However in 2010, Wildlife Institute of India used home-range information obtained from radio-collared tigers and combined this information with camera-trapping data. After the study, density was estimated 4.3 individuals/100 sq km and the number of tiger estimated within a range of 64-90 tigers in Sundarbans Tiger Reserve after extrapolation (Jhala et al. 2011).

 

In 2011, the first initiative was taken when WWF-India, Sundarbans programme, entered the forest of Lothian Wildlife Sanctuary, located at the southern corner of Sundarbans Biosphere Reserve. As a part of the study, first camera traps were deployed on an experimental basis. However, the exercise was washed out with loss of 20 units of camera traps due to inundation by high tides as an effect of the ‘supermoon’. This huge loss is a reminder of the supremacy of nature and the might of the tides. It is necessary to understand the tidal cycles before preparing the final design of a camera-trapping exercise.

 

From the learning and experience in Lothian, the concept of ‘highest point of high tide’ was established, which states that camera-trapping should be started during the high tides because it facilitates finding places with low risk of submergence. With the experiences gained in Lothian, in January 2012, camera traps were first deployed in the tiger forest by the WWF staff in 24 Parganas Forest Division of Sundarban Biosphere Reserve. Sometimes, a strange smell in the air and fresh pugmarks on ground during camera deployment confirms the presence of the felid species. In each trap station, olfactory attractant is applied as it is safe to attract a tiger with the use of olfactory lure. Otherwise, trying to track a tiger in Sundarbans is very dangerous, probably impossible.

 

Eventually, the camera-trapping exercise in reserve forest became the biggest breakthrough in tiger conservation history in Sundarbans. Safe recovery of 98 per cent camera traps after the entire exercise and the estimate of a minimum of 20 tigers from 24 Parganas Forest Division explains the success of the study (Das et al. 2012), as the area was earlier believed to be a non-tiger habitat. This unique study provides necessary information to NTCA to establish standard protocol for camera trapping in Sundarbans and plays a vital role in declaration of 556 sq km area of 24 Parganas South Forest Division as ‘West Sundarbans Wildlife Sanctuary’. Sundarbans forest department has adopted the method of camera trapping, and in 2016-17 season photo-captured 87 tigers after an exercise was conducted in the entire mangrove habitat (TOI 2017). This camera-trapping study not only gives the numbers of tigers, but also investigates the health of the dense mangrove forest.

 

Sundarbans reflects a successful story of wildlife conservation. Here humans and wildlife share the same habitat for their existence. So, naturally, there is also a long history of human-wildlife conflict, and the magnitude of human-tiger conflict is highest (Vyas 2012). Tigers in Sundarbans are well-known for their man-eating behaviour. However, on-ground verification does not support the statement. In the last 30 years, humans were killed inside the forest only when they entered illegally for NTFP collection. There’s only one incident of a tiger straying into the fringe areas and killing a human, and that also was accidental. Based on these evidences we can say that tigers in Sundarbans carry a dual characteristic. Inside the forest they have no mercy, but outside their territory they understand their limits.

 

Due to the fear with which they rule the human heart, this felid species occupies a position of deep respect in cultures of these areas. The socio-economic condition of majority of people in Sundarban is extremely poor. Fishing is the prime livelihood source of villagers. In search of income, villagers often enter the deep forest for fishing or honey collection. Because the best fishing haul and richest supply of honey is found in the depth of the tiger territory, human-tiger conflict is very common in these areas.

 

In this remote and hostile corner of the planet, people believe in supernatural forces that direct and shape their life. Before entering into the jungle, irrespective of religion, people worship ‘Bono Bibi’ (a deity of Sundarbans forest) for protection from the tiger. As they enter into the forest they put themselves at the mercy of one of the most ferocious hunters on earth. Their belief is what they cling on to for survival. People have to risk their lives to make a living in this harsh environment. This is the reality of life in this land. However, the existence of Sundarbans as well that of the tiger in this mangrove is under threat due to the impact of climate change. At this time the question that we must ask is why should we conserve tiger and for whom? What will happen if tigers disappear from their habitat, who will be affected if such a situation arises?

 

We are living in a period when our relationship with nature is not in balance. Due to increasing levels of pollution in air, water, and soil, in the past few decades, climate on earth has changed drastically. It happened because a large part of the planet’s forest area has already vanished, thanks to uncontrolled growth of human civilisation. The impact of global warming is clearly visible in sea-level rise, coastal erosion and dramatic change in salinity.

 

Destruction of mangroves due to anthropogenic pressure is also matter of concern as this region is under intense human disturbance. As Sundarbans is a subsiding delta and the relative sea-level rise is higher compared to other parts of our planet, it will always face threat from all dimensions (Hazra et al. 2002). Already 19,000 acres of forest land have submerged, and, during the last 30 years, four islands have vanished from the map of Sundarban due to rising water level. Some experts believe that due to sea-level rise and increase of coastal erosion the land area of Sundarban has decreased, and it is true. Some try to argue that the decreasing land area and increasing salinity is forcing the tigers to venture out of their habitat. However, this argument still needs to be backed with substantial research. 

 

In the Sundarbans forests, the tiger as an apex predator of the food chain plays a vital role in balancing the ecosystem. That is why, tiger conservation is not just an attempt at saving a charismatic species from the verge of extinction but is also a necessary step for saving human civilisation and planet earth. However, if we really want to save this beautiful animal and its habitat then we have to think beyond only numbers and make this battle not only about the tiger but its habitat holistically.

 

Already four islands have lost their status and the future of many islands is at the mercy of mighty tides. To protect this fragile ecosystem urgent positive steps are required. Increasing the plantation of mangrove will be helpful in diminishing the coastal erosion. Providing other sources of livelihood will reduce the economic dependency on forests, allowing nature to fill the wounds on its own.

 

It is a well-known fact that Sundarbans is a ‘hidden treasure’ and the dense swamp provides protection to tigers. Though many studies have already been done to explain the inside story of this mangrove forest, Sundarbans is still a mysterious haven for nature lovers. In this ecosystem the tiger is a legendary symbol. This charismatic brutal killer is also an integral part of our culture and a witness to the growing human civilisation around its habitat. We have already destroyed many jungles on this planet, and remaining patches like Sundarbans are struggling to survive. This is the time when we must rise and live up to the ‘values of humanity’, the decorated virtue of our culture. Will we with all our might and intelligence be able to save our world? Only time will tell.

 

References

 

Champion, Harold George and S.K. Seth. 1935. A Revised Survey of the Forest Types of India. New Delhi: Government of India.  

 

Das, S. K., P. K. Sarkar, R. Saha, P. Vyas, A. A. Danda, and J. Vattakavan. 2012. Status of Tigers in 24-Parganas (South) Forest Division, Sundarban Biosphere Reserve, West Bengal, India. New Delhi: World Wide Fund for Nature-India.

 

George Wright Society. 2008. ‘UNESCO's Man and the Biosphere Program: What are biosphere reserves all about?’. Online at http://www.georgewright.org/mab
 

Hazra, S., T. Ghosh, R. Das Gupta, and G. Sen. 2002.  Sea Level and associated changes in the Sundarbans. Science and Culture 68: 309-321.

 

Jhala, Y.V., Q. Qureshi, R. Gopal, and P.R. Sinha, eds. 2011. Status of the Tigers, Co-predators, and Prey in India. New Delhi: National Tiger Conservation Authority, Govt. of India; Dehradun: Wildlife Institute of India.

 

Karanth, K.U., J.D. Nichols. 2000. Ecological Status and Conservation of Tigers in India. Final technical report to the Division of International Conservation, US Fish and Wildlife Service, Washington, DC, and Wildlife Conservation Society, New York, USA; Centre for Wildlife Studies, Bangalore, India.

 

National Tiger Conservation Authority Ministry of Environment & Forests and Wildlife Institute of India. 2008. ‘Status of Tigers, Co-Predators and Prey in India.’ Online at http://indiaenvironmentportal.org.in/files/tiger.pdf

 

The Times of India. 2017.  ‘Sunderbans now happy hunting ground for tigers, numbers go up’, The Times of India, Kolkata, June 30.

 

Vyas, P. 2012. ‘Biodiversity Conservation in Indian Sundarban in the Context of Anthropogenic Pressures and Strategies for Impact Mitigation’, PhD thesis. Department of Wildlife Science, Saurashtra University.

 

WWF Tiger Alive Initiative. 2016. Doubling Tigers: WWF Tx2 Annual Report. Kuala Lumpur: World Wildlife Fund for Nature.