Mumbai: Over the past decade or so, Mumbai has lost about 40% of its mangroves due to reclamation, encroachment, and garbage dumping, among other causes. But patches of this resilient plant species still exist, in the Thane and Vasai creeks, and in Mahim, Versova and Gorai. While many commuters are likely to see this unique form of plant life every day, few have a proper understanding of their ecological value to the city.
One of the longest and best-preserved mangrove forests within the city are near the Godrej headquarters in Vikhroli. Last week, ahead of World Environment Day, the Godrej Culture Lab hosted a talk by wildlife photographer Anish Andheria, about how mangroves are one of the city’s major green lungs. Mr. Andheria is president of the Wildlife Conservation Trust, and a member of the Maharashtra State board of wildlife.
Mangroves, Mr. Andheria said, are particularly vulnerable because they grow on the interface between land and sea, which is also where ports are built. Major financial capitals also come up on the coast and Mumbai is one of them. “Back when Mumbai was seven islands, all of the islands were surrounded by mangroves.” He said. “The mangrove forests were home to some of the largest reptilians on earth like the salt water crocodile.”
There are now only 11 true species of mangroves left in Mumbai. Neverthless, Mr. Andheria said, we are lucky that despite being in a sprawling, polluted city, these stretches of mangroves still give people an opportunity to experience wildlife. He mentioned jackals as an example; once a common sight, their numbers have fallen 85%, but you can still find them in the mangroves.
Aside from being home to a large variety of aquatic life and animal species, mangroves are great land-building machines. “There are only two organism that can build land: mangroves and corals. The sea erodes land constantly, and these organisms hold the land in place.” Mangroves, Mr. Andheria said, thrive in the toughest soil conditions and can filter out the salt from sea water. When water from rivers flows into the sea, mangroves that hold the sediment and keep it from being washed away. The water around them therefore is highly nutritious and an ideal breeding ground for various varieties of fish. Their role as nurseries for fish make them crucial to communities like the Kolis, who depend on the mangroves for subsistence, even worshipping them.
Mangroves, Mr. Andheria said, also protect against flooding and natural disasters. “Simply because, by default, their presence means that people would have to live at least a kilometre away from the coast and that could save a lot of lives.”
Marshland also hold 25 times more carbon than normal soil. “When a building comes up for which mangroves need to be destroyed, what people don’t realise is that by removing them you are releasing carbon into the atmosphere that had been stored in them for thousands of years.”
Mangroves also help control pollution as filter out a lot of toxins released into the water by factories; current reports, though, indicate that the toxic load now being released is six-and-a-half times more than they can absorb.
There are myriad reasons, such as the reclamation of land and cutting the mangrove trees for wood, that are slowly depleting mangrove forests in Mumbai. Most important, Mr. Andheria said, was a lack of awareness among citizens about the importance of mangroves. He urged the audience to work with each other and the government to address this gap and spread the message about the importance of mangroves and the range of wildlife that they support.
