When river Ganges changed course from the original Hugli channel to combine upstream with the Brahmaputra , most parts of the 24 Parganas Sundarbans faced increased salinity and this gradually affected the flora and fauna of the area. The era also witnessed devastating cyclones, like the one in 1584, which is reported to have claimed about 2,000,000 living creatures.
The British East India Company set up their headquarters at Calcutta in 1757 at the edge of the Sundarbans. The forests at that time stretched uninterrupted for 19,200 square kms and retained much of their splendor and diversity.
In 1928 the British Government assumed proprietary rights to the forest and, in 1830, began leasing out tracts of the forests for reclamation ~ a process which continued until 1875-76.
By 1873 nearly 5,100 square kms of forests had been converted into agricultural land and the Sundarbans area forest cover had been effectively reduced to about 14,100 square kms. In 1875-1876 the government declared un-leased forest reserved, and placed them under the jurisdiction of the Forest Department– a move which created today's Sundarbans forest.
A variety of wildlife survived till the latter part of the 19th century despite the rapid depletion of habitat. Hunter records
A variety of wildlife survived till the latter part of the 19th century despite the rapid depletion of habitat. Hunter records
"Tigers, leopards, rhinoceros, wild buffaloes, wild hogs, wild cats, barasinga, spotted deer, hog deer, barking deer, and monkeys are the principal varieties of wild animals found in Sundarban" in 1875. But the events of the next few decades led to the near complete destruction of the grasslands and rainforests, which coupled with the increase in salinity spelt the death knell for the rhinoceros, leopard, wild buffalo, swamp deer and hog deer Only the tiger, wild pig and spotted deer survived the mass species extinction
From the early of the 20th century, the Sundarban forests were managed using Curtis's working plan which focused on scientific harvesting. This plan was in effect when partition divided the administration of the Sundarbans between Bangladesh ) and India . Both countries continued to protect the area after independence.
The Bangladesh forests in the 24 Parganas by then had been seriously denuded by years of felling and the lack of adequate fresh water. In 1963 and 1973 Sundarbans were allowed to clear reserve forests for agriculture and settle in areas like Jharkhali and Herobhanga islands when refugees from
In 1973, management of a large portion of the Indian Sundarbans was passed on to Sundarbans Tiger Reserve, which was established in 1973 under "Project Tiger. In 1977, it declared Sundarbans a Wildlife Sanctuary and elevated parts of it to the status of a National Park on 4th May 1984. UNESCO inscribed the Indian Sundarbans on the World Heritage List in 1987 and the entire Indian Sundarbans area was recognized by UNESCO as a Global Biosphere Reserve in 2001.