Though the mud crab is considered as one of the nature’s “ecosystem engineers” for its ability to facilitate habitats and nutrients to other species, a significant proportion of its population is being wiped out every year due to its indiscriminate collection along the coastal belt, particularly in the Sundarbans.
The export of this crab has sharply increased over the last decade, leading to the intensification of the onslaught on the wild species, which is also known as mangrove crab, green crab, shila kakra, or by the scientific name of Scylla Serrata.
Environmentalists warn that a depletion of mud crab population will lead to a severe degradation of soil, water, plants and animals in the mangrove and recommend government’s steps to restrict the crab hunting.
Dr Monirul H Khan, a zoology professor at Jahangrinagar University, told the news agency, “The boost in crab export, particularly after the introduction of crab fattening, is taking its toll on the mud crabs of the Sundarbans.”
According to Export Promotion Bureau, Bangladesh exported 3,550 tonnes of crabs in 2011-12, earning Tk 59.24 crore. The export of crabs and eels has increased 30 times from 2000 to 2011, show records at the Department of Fisheries.
The depletion of mud crab population will, first and foremost, lead to pollution of mangrove water bodies, Prof Monirul said. “As detrivores (eaters of dead things), mud crabs clean and destroy stuffs that can pollute the water.
He said if the government wanted to promote the export of mud crabs it should introduce hatcheries and nurseries like India, Myanmar and Thailand for cultivation of farm varieties rather than allowing its collection from the wild.
“To be more precise, mud crab hunting during its breeding period should be banned. The forest department this year banned the collection of mud crabs from the Sundarbans during the breeding period from January to February, but it failed to curb the crab hunting due to a lack of enforcement,” he said.
Krishnendu Shaha, chief fisheries extension officer at the Department of Fisheries, said 6.3 lakh hectares of land adjacent to the 710km-long coastline in the country was identified as extensive mud crab collection zone.
The commerce on crabs depends largely on natural sources, as Bangladesh is yet to adopt farm-breeding of crabs like other crab exporting countries, he said.
-With UNB/The Daily Star input
