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The Sundarbans are the largest mangrove delta of the world, formed from sediments deposited by the Ganges, Brahmaputra and Meghna. They encompass hundreds of islands, with a maze of innumerable rivers, rivulets, and creeks.
60% of the delta is located in Bangladesh, and 40% in India. The name ‘Sundarban’ means “beautiful forest” and it is believed to be derived from a mangrove tree species ‘Sundari’ (Heritiera fomes). The Sundarban mangroves provide a wide spectrum of ecosystem services, including improvement of air quality, stabilising temperature, reduction of ultraviolet radiation, oxygen generation, carbon sequestration, and support for exceptional biodiversity. Click to learn more about mangroves!
It contains two UNESCO World Heritage Sites (WHS), namely The Sundarbans (Bangladesh) and Sundarbans National Park (India), both inscribed in 1987. It also contains two Ramsar sites (Wetlands of International Importance) under the terms of the Convention on Wetlands, specifically Sundarbans Reserved Forest (Bangladesh, designated in 1992) and the Sundarban Wetland (India, designated in 2019).
The mangrove forests act as a natural shelter belt and protect the hinterland from storms, cyclones, tidal surges, sea water seepage and intrusion. The mangroves serve as nurseries to shell fish and fin-fishes and sustain the coastal fisheries of the entire eastern coast. Click to learn more about peat!
It supports exceptional biodiversity in its terrestrial, aquatic and marine habitats; ranging from micro to macro flora and fauna.
They are a Tiger Conservation Landscape of global priority, as it is the only mangrove habitat which supports a significant tiger population (Panthera tigris tigris).
They are home to a large number of endangered and globally threatened species including the fishing cat (Prionailurus viverrinus), saltwater crocodile (Crocodilus porosus), Gangetic or South Asian river dolphin (Platanista gangetica) and Irrawaddy dolphin (Oracella brevirostris), King cobra (Ophiophagus hannah), and many bird species; eight out of the twelve kingfisher species recorded in India are found here.
In addition, two out of the four known species of the living fossil, the horseshoe crab, are found in the Sundarbans, (Tachypleus gigas and Carcinoscorpius rotundicauda).
Outstanding Universal Value (OUV)
The Sundarbans is the largest area of mangrove forest in the world and the only one that is inhabited by the tiger. It represents the process of delta formation and the subsequent colonization of the newly formed deltaic islands and associated mangrove communities. Its role as a wetland nursery for marine organisms and as a climatic buffer against cyclones is a unique natural process
The Sundarbans are also an area of exceptional marine and terrestrial biodiversity, with immensely rich mangrove flora and mangrove-associated fauna, including significant populations of globally endangered cat species, such as the Bengal Tiger. It contains 78 species of mangroves, making it the richest mangrove forest in the world. It is also unique as the mangroves are not only dominant as fringing mangroves along the creeks and backwaters, but also grow along the sides of rivers in muddy as well as in flat, sandy areas.
Identification of Threats
The most serious threats are due to climate change and global overheating, resulting in rising sea levels, an increase in the frequency and severity of extreme weather events such as storms and tidal surges, and increased salinity. Such threats occur frequently and cause direct damage, not to mention its irreparability. As such, the risk rating is considered to be high when pinned against the framework for threat assessment.
The wider Sundarbans forest is experiencing extensive coastal erosion and retreat, largely due to increased frequency of storm surges and other extreme natural events, rise in sea-level and increased salinity. With sea-level rise, increased salinity will result in ecological succession to more salt tolerant species, reducing mangrove biodiversity.
Salinity rise and nutrient limitation negatively affect the mangrove forest's structure and cause decline of forest coverage, with salinity-sensitive species such as the threatened Ganges river dolphin and Irrawaddy dolphin gradually disappearing. This also represents a potentially great loss of carbon storage (Rahman et al., 2010), and loss of habitat for important biodiversity such as the Bengal tiger.
By the end of 2100, if current trends are not reversed, temperatures could rise by 2.6 - 4.8 C. With the accompanying rise in sea levels of 59 cm, the Sundarbans will be underwater. This would affect the lives of millions of people in Sundarbans, the Ganges basin, and Kolkata, as well as billions of dollars worth of property and infrastructure. Secondary effects include drought, disease, poor air quality, famine and mass displacement.
The most serious threats caused directly by human activity are interference with the flow of water in the Ganges which has reduced the flow of fresh water into the delta, resulting in increasing salinity, and the discharge of pollutants into the feeding rivers. Such threats occur frequently and cause direct damage, not to mention its irreparability. As such, the risk rating is considered to be high.
Erosion across the Sundarban islands is more dominant than the accretion. Due to this, the Sundarbans are now almost half the size of the area that existed in the late 1800s. The eastward migration of the Ganges River is causing a long-term ecological change in the entire Sundarbans forest. This process has intensified due to the increased diversion of freshwater sources to the Sundarbans forest that occurred in recent years; up to 40% of the dry season flow of the Ganges was diverted upstream after the creation of the Farraka Barrage in 1974. Siltation is also a problem and specific channels are becoming severely blocked and could soon be considered unnavigable.
There are many other threats including over-exploitation (such as deforestation & large scale conversion of mangroves to shrimp farming), altered hydrology, pollution, poor fishing practices and poaching of high value species.
The transboundary Sundarbans is also home to a growing population of about 7.2 million people of which about 2.7 million live in Bangladesh and the rest in India. Half of the population in the vicinity of Sundarbans is landless and they are almost entirely dependent on rain-fed agriculture and subsistence fishing. High risk investment due to frequent cyclones and flooding makes any other industrial investment practically non-existent, especially in the forest adjoining sub-districts.
The site’s ecological and biodiversity values are all affected by these pressures and the Outstanding Universal Values of the site are therefore under serious threat in the future.
Assessment of Conservation Management Plans
The Sundarban ecosystem is located in two countries, and transboundary cooperation could be enhanced. Several formal / informal bilateral monitoring mechanisms exist, but a formalised joint management and surveillance protocol of the World Heritage site has yet to be formulated.
Staffing is a major concern. According to the 2020 report for the Indian Sundarbans, there are vacancies of more than 50% in frontline staff. 60% of the staff are over 50 years old, leading to patrolling limitations in the extreme conditions of the region.
The IUCN report also found that to some extent, multiple designations may lead to 'work in silos' and conflicting objectives (e.g. the objective to create inviolate areas for tigers under the Tiger Reserve concept and the idea to support people's livelihood under the Man-and-Biosphere program). This is not surprising given the complexity of problems faced in the region, which would be challenging even for the wealthiest of countries.
The sustainable use of the region by its inhabitants is also a challenge to manage, especially given the combination of population growth, poverty, and environmental challenges.
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Suggested Conservation Management Strategies
Some of the problems facing The Sundarbans, such as rising sea levels, are beyond the capability of regional authorities. However, there are other serious threats to The Sundarbans which originate directly from human activity.
For example, the discharge of industrial and domestic waste into watercourses is a major threat to the ecosystem which needs to be controlled. A more ecologically-sustainable approach to the management of the watercourses feeding the delta is needed. The construction of coal fired power stations such as the one at Rampal in Bangladesh will result in serious air pollution.
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Such anthropogenic threats must be curtailed at the national and regional level.
Improved transboundary cooperation between India and Bangladesh will help to manage what is a single ecological region which is split between two countries. At the regional level, the transboundary aspect of The Sundarbans as a 'single unit' needs to be codified and integrated into legislation and management practices.
All regulations and policies regarding climate change, environment, conservation, World Heritage and tourism should be compiled under a single transnational coordinating strategy for the entire region.
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Given the tendency to “work in silos” noted in the IUCN report, the formation of multidisciplinary teams would be helpful. However this would be challenging to set up given the severe shortages of frontline staff.
The End.
Bibliography
Akter, Jakia, Maminul Haque Sarker, Ioana Popescu, and Dano Roelvink. ‘Evolution of the Bengal Delta and Its Prevailing Processes’. Journal of Coastal Research 32, no. 5 (September 2016): 1212–26. https://doi.org/10.2112/JCOASTRES-D-14-00232.1.
‘AR6 Climate Change 2021: The Physical Science Basis — IPCC’. Accessed 1 November 2021. https://www.ipcc.ch/report/sixth-assessment-report-working-group-i/.
Donato, Daniel C., J. Boone Kauffman, Daniel Murdiyarso, Sofyan Kurnianto, Melanie Stidham, and Markku Kanninen. ‘Mangroves among the Most Carbon-Rich Forests in the Tropics’. Nature Geoscience 4, no. 5 (May 2011): 293–97. https://doi.org/10.1038/ngeo1123.
Gramling, Carolyn. ‘Rapid Sea Level Rise Could Drown Protective Mangrove Forests by 2100’. Science News (blog), 4 June 2020. https://www.sciencenews.org/article/sea-level-rise-mangrove-forests.
Knutson, Tom. ‘Global Warming and Hurricanes’. Accessed 1 November 2021. https://www.gfdl.noaa.gov/global-warming-and-hurricanes/.
McIvor, Anna, Tom Spencer, Iris Möller, and Mark Spalding. ‘The Response of Mangrove Soil Surface Elevation to Sea Level Rise’. Natural Coastal Protection Series: Report 3. Cambridge Coastal Research Unit Working Paper 42. The Nature Conservancy and Wetlands International, 2013. https://www.wetlands.org/publications/the-response-of-mangrove-soil-surface-elevation-to-sea-level-rise/.
Spalding, Mark. ‘Mangroves as Incredible Carbon Stores’. Cool Green Science, 11 October 2013. https://blog.nature.org/science/2013/10/11/new-science-mangrove-forests-carbon-store-map/.
‘Sundarbans Reserved Forest | Ramsar Sites Information Service’. Accessed 1 November 2021. https://rsis.ramsar.org/ris/560.
The International Union for Conservation of Nature. ‘Sundarbans National Park’. IUCN World Heritage Outlook. IUCN, 2020. https://worldheritageoutlook.iucn.org/explore-sites/wdpaid/14177.
UNESCO World Heritage Centre. ‘The Sundarbans’. UNESCO World Heritage Centre. Accessed 1 November 2021. https://whc.unesco.org/en/list/798/.
UNESCO World Heritage Centre. ‘Sundarbans National Park’. UNESCO World Heritage Centre. Accessed 1 November 2021. https://whc.unesco.org/en/list/452/.
Union of Concerned Scientists. ‘Kolkata, West Bengal, India’. Climate Hot Map. Union of Concerned Scientists, 2011. https://www.climatehotmap.org/global-warming-locations/kolkata-west-bengal-india.html#end21;
International Peatland Society. ‘What Is Peat?’ Accessed 1 November 2021. https://peatlands.org/peat/peat/.
Zimmer, Katarina. ‘Mangrove Restoration Frustration’. Hakai Magazine, 7 September 2021. https://www.hakaimagazine.com/features/mangrove-restoration-frustration/.