DHAKA, Nov. 18 (Xinhua) -- The flora and fauna of Bangladesh's southwestern Sundarbans, the world's largest mangrove forest, became a major casualty of Thursday's devastating cyclone that roared out of the Bay of Bengal.

    Experts fear that much of nearly 40 species of mammals, some 400 species of birds and more than 200 species of fishes fell victim to the calamity -- one of the worst in recent memory.

    The Sundarbans, about 350 km southwest of capital Dhaka, is the home of the Royal Bengal Tiger, already an endangered animal, as well as of many other species like Spotted Deer which are on the verge of extinction.

    They said the Forest Department is yet to make any assessment of the colossal losses of the wildlife in the Sundarbans, declared as a world heritage site by UNESCO.

    Over a million people living in and around the Sundarbans depend on the forest for their livelihood. "But most importantly, the forest was an environmental shield for the people living in the country's southwestern region," Prof. Anwarul Islam of Zoology Department of Dhaka University told Xinhua Sunday.

    Prof. Islam, who is chief executive of Wildlife Trust of Bangladesh (WTB), stressed the need for assessing the loss caused to the Sundarbans and taking immediate measures to save the wildlife.

    But this could prove a difficult task, he said, pointing out the lack of expertise, technical preparation and logistics.

    Sources in the Sundarbans areas said that a good number of bodies of Spotted Deer and monkeys were seen floating in the rivers and canals in the Sundarbans areas.

    The rivers in the estuary of the Sundarbans hold more than 200 species of fishes including Bangladesh's national fish Hilsha, Fatty Catfish, Bass, White Grunt, Eel Tail Catfish, Indian Salmon, Mullets, Ribbon Fish, Bombay Duck, Anchovys etc.

    Besides, these rivers were the sanctuary of various types of shrimps like tiger shrimps, giant fresh water prawn, Indian white shrimp, green tiger shrimp, brown shrimp among others.