[10] Despite a total ban on all killing or capture of wildlife other than fish and some invertebrates, there has been a consistent pattern of depleted biodiversity or loss of species in the 20th century, with the ecological quality of the forest declining.

The forest is also suffering from increased salinity caused by sea level rise due to effects of climate change and reduced freshwater supply.

[18] A ruin of an abandoned city was found in the Baghmara Forest Block that is attributed to Chand Sadagar, a pre-Mauryan semi-historical figure in Bengali folklore.

[19] Archaeological excavation at Kapilmuni, Paikgacha Upazilla, north of the Sundarbans in Bangladesh, revealed ruins of urban settlement dating back to the early middle ages.

[19] In 1757, The British East India Company obtained proprietary rights over Sundarbans from the Mughal Emperor Alamgir II and completed mapping the area in 1764.

[21][22] The Sundarban forest lies in the vast delta on the Bay of Bengal formed by the super-confluence of the Hooghly, Padma (both are distributaries of Ganges), Brahmaputra and Meghna rivers across southern Bangladesh.

Additionally, the Mangroves species present in the Sundarban area serve a crucial function as a protective barrier for the millions of inhabitants in and around Kolkata, Khulna and Port of Mongla against the floods that result from the cyclones.

To the south the forest meets the Bay of Bengal; to the east it is bordered by the Baleswar River and to the north there is a sharp interface with intensively cultivated land.

The physiography is dominated by deltaic formations that include innumerable drainage lines associated with surface and subaqueous levees, splays and tidal flats.

[32] Robert Scott Troup suggested that succession began in the newly accreted land created by fresh deposits of eroded soil.

[21] The Sundarbans flora is characterised by the abundance of sundari (Heritiera fomes), gewa (Excoecaria agallocha), goran (Ceriops decandra) and keora (Sonneratia apetala) all of which occur prominently throughout the area.

[39] Most importantly, mangroves are a transition from the marine to freshwater and terrestrial systems, and provide critical habitat for numerous species of small fish, crabs, shrimps and other crustaceans that adapt to feed and shelter, and reproduce among the tangled mass of roots, known as pneumatophores, which grow upward from the anaerobic mud to get the supply of oxygen.

[39] Forest inventories reveal a decline in standing volume of the two main commercial mangrove species – sundari (Heritiera spp.)

[47][48] Despite a total ban on all killing or capture of wildlife other than fish and some invertebrates, it appears that there is a consistent pattern of depleted biodiversity or loss of species (notably at least six mammals and one important reptile) in the 20th century, and that the "ecological quality of the original mangrove forest is declining".

The physical development processes along the coast are influenced by a multitude of factors, comprising wave motions, micro and macro-tidal cycles and long shore currents typical to the coastal tract.

Erosion and accretion through these forces maintains varying levels, as yet not properly measured, of physiographic change whilst the mangrove vegetation itself provides a remarkable stability to the entire system.

One of the greatest challenges people living on the Ganges Delta may face in coming years is the threat of rising sea levels caused mostly by subsidence in the region and partly by climate change.

A 1990 study noted that there "is no evidence that environmental degradation in the Himalayas or a 'greenhouse' induced rise in sea level have aggravated floods in Bangladesh"; however, a 2007 report by UNESCO, "Case Studies on Climate Change and World Heritage" has stated that an anthropogenic 45-centimetre (18 in) rise in sea level (likely by the end of the 21st century, according to the Intergovernmental Panel on Climate Change), combined with other forms of anthropogenic stress on the Sundarbans, could lead to the destruction of 75 percent of the Sundarbans mangroves.

[51] In a study conducted in 2012, the Zoological Society of London (ZSL) found out that the Sunderban coast was retreating up to 200 metres (660 ft) in a year.

This, coupled with an around 1.5 °C (2.7 °F) rise in surface water temperatures and increased levels of salinity have posed a problem for the survival of the indigenous flora and fauna.

The study contended that poor planning on the part of the India and Bangladesh governments coupled with natural ecological changes were forcing the flight of human capital from the region[55][56] According to a report created by UNESCO, the landfall of Cyclone Sidr damaged around 40% of Sundarbans in 2007.

[75] A number of industries (e.g., newsprint mill, match factory, hardboard, boat building, furniture making) are based on raw materials obtained from the Sundarbans ecosystem.

Non-timber forest products and plantations help generate considerable employment and income opportunities for at least half a million poor coastal people.

Five species of marine turtles frequent the coastal zone and two endangered reptiles are present – the estuarine crocodile and the Indian python.

Sundari trees (Heritiera fomes) dominate the flora, interspersed with Gewa (Excoecaria agallocha) and Passur (Xylocarpus mekongensis) with Kankra (Bruguiera gymnorhiza) occurring in areas subject to more frequent flooding.

There is an understory of Shingra (Cynometra ramiflora) where, soils are drier and Amur (Aglaia cucullata) in wetter areas and Goran (Ceriops decandra) in more saline places.

Sajnakhali Wildlife Sanctuary is a 362-square-kilometre (140 sq mi) area in the northern part of the Sundarbans delta in South 24 Parganas district, West Bengal, India.

The Bengali folk epic Manasamangal mentions Netidhopani and has some passages set in the Sundarbans during the heroine Behula's quest to bring her husband Lakhindar back to life.

The plot centres on a headstrong American cetologist who arrives to study a rare species of river dolphin, enlisting a local fisherman and translator to aid her.

The Sunderbans has been the subject of a detailed and well-researched scholarly work on Bonbibi (a 'forest goddess' venerated by Hindus), on the relation between the islanders and tigers and on conservation and how it is perceived by the inhabitants of the Sundarbans,[82] as well as numerous non-fiction books, including The Man-Eating Tigers of Sundarbans by Sy Montegomery for a young audience, which was shortlisted for the Dorothy Canfield Fisher Children's Book Award.