While speaking of mangrove forests, it is easy for the mind to wander to the vast mangroves of Sunderbans or the dense mangroves of the Andaman Islands. But mangroves are present all along the coast and even surround a bustling metropolitan like Mumbai. Explore this ecosystem of the island city as the author shares some of the threats faced by these urban mangrove forests.
The Mithi River of Mumbai drains into the Mahim creek, after flowing for about 15 km through the city. This estuary that runs between the Bandra and Mahim areas of the city essentially divides the city into its two administrative districts i.e. the Mumbai city to the south and Mumbai suburban to the north. On a train journey between the Bandra and Mahim stations, one crosses the Mithi River at a point where it joins the Mahim creek. Upstream, the Bandra-Kurla Complex business centre emerges in the distance. To the west, the Swami Vivekanand Road joins the Mahim Causeway – an important link between Bandra and Mahim, which was built in 1846 by a generous donation of `1,57,000 by Lady Jeejeebhoy. As the local train chugs along southwards, a dash of green makes an appearance on the scene. One of the last remaining patches of mangroves stands guarding the banks of the river silently, as the city continues its rapid growth.
Mangrove forests harbour diverse biodiversity. Seen here is a flock of migratory birds near the mangroves adjacent to the Maharashtra Nature Park Society in Dharavi.
Fading in the distance?
Mangrove plants are known for their hardy nature due to their capacity to survive in a highly saline environment. In Mumbai, you can see the mangroves lining the intertidal zones across the island’s coast. On a birding trip to Sewri, as you walk down to the jetty to see the visiting pink beauties, i.e., the flamingos, you will notice some pointy stubs poking out of the mud along the mangroves’ stretches. These are pneumatophores or the breathing roots of the mangroves, reaching out of the surface to seek oxygen.
Mangroves around the Mithi River are probably the most threatened, as the water of the river is getting polluted by the day and the land is being reclaimed for ‘developmental’ projects.
Mangrove patches in Mumbai cover an area of about 45 sq. km. and out of the 35 species of mangroves found in India, this city plays host to 12 of them. These mangrove forests of Mumbai are one of the most threatened in the world. The mangroves play a vital role in maintaining the ecological balance of the coastal city, however, the growing metropolis exerts enormous pressure on these specialised forests. Their importance has been underscored by the fact that the Forest Department of Maharashtra has accorded them with the status of a ‘protected forest’, which makes their destruction an offence.
Several freshwater aquatic birds, such as the Common Kingfisher, are often seen in the mangroves during low tide.
A coastal city anywhere in the world is vulnerable from the hazards of the sea. Storm surges, cyclones, tsunamis – all could wreak havoc on the lives and property of its inhabitants. However, mangrove forests act as natural barriers and lower the impact of such natural calamities. When the tsunami of 2004 hit southern India, certain hamlets around the Pichavaram area in Cuddalore district of Tamil Nadu were protected from its impact because of the thick mangrove cover. The mangroves of Mira-Bhayander and Lokhandwala-Versova areas in Mumbai face the western sea and could buffer a larger part of the city in much the same way.
One might argue that the western coast of India might not be as prone to cyclones and tsunamis as its eastern counterpart is, but this protection is not the only function of a mangrove system. They also prevent land erosion and inhibit the sea from making inroads onto the land. In other words, they keep the city intact.
Sewri Bay, famous wintering grounds of the flamingos, are surrounded by mangroves that provide shelter for the magnificent birds during high tide.
But these are its more conventionally well-known functions. An International Union for Conservation of Nature (IUCN) report indicates that mangroves have more biomass than tropical forests and sequester carbon better in a far smaller area. They enrich soils with carbon by trapping the atmospheric CO2, which leads to the formation of peats. This trapped carbon is known as ‘coastal blue carbon’. Thus, the destruction of mangroves results in releasing large amounts of carbon dioxide back into the atmosphere.
Who will save the saviour ?
As the city continues to grapple with a scarcity of space, mangrove forests are seen as soft targets. Although the High Court of Bombay has time and again reinforced the laws protecting this precious natural habitat, violations of the law are not uncommon. The Coastal Regulatory Zone (CRZ) notification of 2011 classifies mangroves under CRZ-I, ensuring them complete protection against their destruction for any construction activity, apart from the Greenfield airport at Navi Mumbai, which unfortunately will result in the loss of over 400 acres of mangroves.
While the strict implementation of the current protection laws is the need of the hour, effective involvement by the citizens of Mumbai will also go a long way in protecting these valuable forests. An outing to the Bhandup Pumping Station, which lies close to the Eastern Express Highway and the Mulund-Airoli Bridge, will enable a visitor to witness the sheer biodiversity that mangroves can support. A variety of avifauna, including migratory and resident species, can be easily spotted. Jackals and mongooses are generally sighted in the wee hours of the morning. On the muddy forest floor, fiddler crabs, mudskippers and several species of molluscs can be seen foraging. Similarly, bird-watching sessions at Sewri mudflats, Uran and Navi Mumbai also go a long way in helping people appreciate the biodiversity of mangroves.
In addition to taking part in such events, one must stay vigilant and report any destruction of mangroves in the vicinity, by the way of cutting of trees or dumping debris or garbage. Destruction of mangroves typically makes way for construction projects. Leading the awareness drive about mangroves is the Mangrove Cell of the Maharashtra Forest Department, headed by an officer of the rank of Chief
Conservator of Forests. Equipped with a sleek user-friendly website, it is working on outreach programmes and conservation efforts with an aim to increase the mangrove forest cover of the state. It also runs projects in collaboration with international agencies and invites individuals to contribute in conservation efforts in various capacities.
There is no doubt that the benefits of a healthy mangrove ecosystem are numerous – to an individual, to a city, and to the planet as a whole. The satisfaction of seeing a thriving ecosystem, complete with a fully functional food-web is unparalleled. However, developmental pressures on the city are continually rising and this ecosystem is already bearing the brunt. It is thus imperative that no efforts are spared to conserve the mangroves of Mumbai, for in their well-being, lies our secure future.
Image credit for all images: Adithi Muralidhar
This article was first published in the May 2015 edition of Saevus Magazine