The'Sundarbans'at the world's largest delta-face of Bhagirathi-Hooghly river system of India,declared as'World Heritage Site'(1984) for the largest mangrove concentration and only mangrove tiger-land in the world shows wide range of natural forest and aquatic resources co-exising as the most complex 'Mangrove Food-Web'. Extensive base of Mangrove Food Pyramid is formed by huge reserve of phytoplanktons under water and forest detritus on land with Royal Bengal tigers at the pinnacle.Anthropogenic interference in form of Bheri-culture resulted in severe over-exploitation of aquatic resources in northern Sundarbans.Poor female and minors indiscriminately collect various microspecies by mosquito-nets from daily tides and sort out only prawn seedlings for bheries as stocking materials destroying millions of other ecologically valuable juveniles thrown on coastal sand.Though it is only way of sustenance of local poor it is suspected to narrow down broad base of mangrove food pyramid gradually towards ultimate collapse posing great threat to all top consumers,even human existence.The paper assessed severe ecological impact of bhericulture suggesting proper Environmental Management Plan.