The subtropical gyre in the Bay of Bengal, the 2.1-million sq-km body of water bounded by India, Bangladesh and Myanmar and featuring some of the world’s most beautiful beaches, is filling with thousands of tonnes of plastic and other pollutants, according to a study by the US-based National Bureau of Asian Research. The enormous bay faces other problems as well including a giant oxygen-free dead zone and the destruction of habitat along its boundaries.
The bay, the biggest water region called a bay in the world, is fed by the Ganges, the Brahmaputra, the Irrawaddy and other major rivers that pour off the Himalaya mountain ranges, bringing huge amounts of the pollutants off some of the world’s most densely populated -- and polluted -- countries. Nearly 400 million people depend upon it for animal protein.
With a combined population of 1.7 billion and sustained GDP growth currently of $3 trillion, the bay’s survival depends on the ability of states to enhance sub-regional cooperation. A quarter of the world’s traded goods cross it, including huge volumes of Persian Gulf oil and liquefied natural gas. Eventually, if the accumulation of trash continues to grow, it will impede shipping, according to the report. Given its transboundary nature, environmental damage to the Bay of Bengal cannot be mitigated by a single country and will require mitigation through collective action, according to the report.
The heavily-footnoted report, which can be found here, titled “Bangladesh’s role n Forging a Bay of Bengal Community,” was authored by Tariq A. Karim, the former Bangladesh high commissioner to India. It calls on Bangladesh, which is “uniquely positioned to take on a bridging role among the littoral states” with the introduction of the Bay of Bengal Initiative for Multi-Sectoral Technical and Economic Cooperation, an international organization of seven nations of South and South East Asia, to handle a growing series of problems in the region. Indonesia and Malaysia must be included in the cooperative effort.
The organization must, despite the political gridlock among current Bay of Bengal managers, cooperate to ensure self-preservation and an improved quality of life for all in the region. As a starting point, the threat from emerging ecological burdens, as opposed to other more politically divisive challenges, would be the ideal place to begin building a framework for sub-regional cooperation.
These three major ecological risks in particular present immediate need for collective action: accumulation of plastic waste, the existence of dead zones, and destruction of mangrove forests.
“The unique characteristics of the southern Indian Ocean—the Asian monsoon season and the strength of southeast trade winds exceeding the trade winds of the Pacific and Atlantic Oceans—all combine to push floating plastic material farther to the west,” Karim writes.
Along with coastal Australia and the Mediterranean Sea, the bay joins five so-called major gyres containing an estimated 5.25 trillion pieces of plastic weighing 269,000 tonnes. It has been said that by 2050, the weight of plastic, if nothing is done, will outweigh the weight of fish in the world’s oceans. The five are the North Pacific, North Atlantic, South Pacific, South Atlantic and Indian Ocean gyres. They are massive, slowly rotating whirlpools that accumulate marine debris and especially plastics which do not wear down. They simply break into tinier and tinier pieces that will remain in the ocean for decades or longer, too often being mistaken by food for sea life.
Since 1997, other studies show, nearly 700 species of marine animals have had some sort of interaction with human-made debris that hastens their journey toward the International Union for Conservation of Nature red list marking them for extinction. Up to a million seabirds and 100,000 marine mammals and sea turtles die each year from eating plastic, according to the organization.
he Bay of Bengal is rich in marine resources and produces 6 million tons of fish that correspond to nearly 4 percent of the total global catch. It is an important source of animal protein for nearly 400 million people in this region. But the Bay is heavily littered with plastics and huge amounts of plastic waste are found on the shorelines, on the seabed, and suspended in the water column. The corals of St. Martin Island are almost dead, littered with marine debris, plastic packages, and food wrap discarded by hundreds of tourists daily. The Bay of Bengal and the South China Sea are the new plastic hotspots in Asia. Every year about 2 lakh tons of plastics enter the Bay of Bengal from Bangladesh. According to the Earth Day Network of USA (2018), Bangladesh is the 10th most plastic polluting countries in the world. Population pressure, poor waste management practices and shipbreaking are primarily responsible for that. Every year, 60-65 ships are broken in Chattogram and Khulna.
The trash is accumulating in the Bay of Bengal due to due to movement from the southern Indian Ocean northward and continuous drainage from the major eastern Himalayan rivers and “will grow to alarming proportions if no actions are taken and will contribute to the formation of ‘plastic soup’ as well as perhaps aggravating existing dead zones and other ecological challenges.”
Among those ecological challenges is a dead zone that spans 60,000 square kilometers occupying water depths of 100 to 400 meters, directly affecting available fish stocks by depleting the habitable ecosystem of fisheries.
Another study estimates that up to 90 percent of the global riverine input of plastic waste originates from Asia. The input of plastics to the Southern Indian Ocean is mainly through Indonesia. The Australian contribution is small. While there is little plastic in the southern Indian Ocean, it appears that ocean currents spin the trash northward, concentrating it in the bay.
“Of the nearly 200 million people living along the coastlines, a majority are either partially or wholly dependent on the bay’s fisheries,” according to the report. “On a global scale, the dead zone…has the potential of disrupting the global nitrogen cycle. Worsening conditions in the dead zone would trigger a drain of nitrogen—a key nutrient for life—in the planet’s oceans.”
The coasts of the bay face significant loss of mangrove forests in South and Southeast Asia. In Myanmar, mangroves were once extensive, but are now reduced to the Rakhine and Tanintharyi States and the Irrawaddy Delta. The forest belt along the Arakan coast near Bangladesh has been vastly reduced as a result of industrial and agricultural runoff and conversion of forests into land for commodity cash crops.
Mangroves, as the report notes, have traditionally served as a protective wall against severe weather for littoral states. As climate change continues to intensify storms globally, further recession of the natural protective barrier will leave littoral states vulnerable to the destructive capacity of such storms.