The Conservation Action Trust and Mangroves

  • What are mangroves?
  • Mumbai’s mangroves
  • CAT and mangroves

What are mangroves?

Wetlands have immense ecological importance and mangroves are one of the most fascinating wetland plants. Mangroves are particularly important as buffer between the land and the sea. They protect fragile coastlines from erosion, effectively control floods, provide a variety of fish and clean coastal waters.
Mangrove ecosystems are a peculiar habitat covering the transition zones between the tropical land and sea.  In the mangrove forests one can see how a tropical rainforest (Jungle) gets transformed into a Mangle (forest in marshes). They grow on clayey soil, which is flat and sloping gently (mudflats), and in the region where tidal action brings in water regularly.  Mangroves are found extensively in the estuarine regions where salt water mixes well with the fresh water.  Besides estuaries, they also inhabit inter tidal regions of shallow bays and creeks where the environment is conducive for the growth of mangroves.
The Indian mangroves comprise approximately 59 species in 41 genera and 29 families. Of these, 34 species belonging to 25 genera and 21 families are present along west coast. There are basically 6 types of mangrove forests. They are:

  • Over wash mangrove forests: These are small islands covered with mangroves that are frequently washed by the tides. The dominant species is Rhizophora or the red mangrove.
  • Fringing mangrove forests: These strips of mangroves are found along waterways and are covered by daily tides. The dominant species is red mangrove.
  • Riverine mangrove forests: These are luxuriant stands of mangroves along tidal rivers and creek with a good input of fresh water. Often comprises red mangrove, grey mangrove, mangrove apple, etc
  • Basin mangrove forests: These are stunted mangroves located in places such as the interior of swamps, often dominated by Avicennia or the Grey mangrove.
  • Hammock mangrove forests: Similar to basin mangrove forests but are found in more elevated sites
  • Scrub mangrove forest: A dwarfed stand of mangroves found on flat coastal fringes.

Mumbai’s mangroves

Mumbai is a reclaimed mass of islands. As there is little original land and sea from all sides, Mumbai is vulnerable to sea erosion. The only cost effective way to save Mumbai from erosion and delay the impacts of the rising sea level is to protect its mangroves. If given time, the mangroves will not only save the city from erosion but will also slowly create more land by pushing the sea back gently and keep the ill effects of the sea farther away.

Mumbai has gone through many cycles of mangrove deforestation and land reclamation and during this time the mangrove cover of Mumbai has been brought to less than one third of its original amount. However, large continuous areas of mangrove cover are seen today in Mumbai along the Vasai Creek, Thane Creek, Manori and Malad, Mahim - Bandra, Versova, Sewri, Mumbra - Diva and few other places. It is essential these areas are protected from damage.

Around 18 out of the 35 species of true mangroves found in India have been identified along the Maharashtra coast and 13 species of these are found in Mumbai. However, one species that really dominates the Mumbai coastline is Avicennia marina, mainly due to uniformly high salinity across the region.

CAT and mangroves

Debi Goenka started a humble campaign on saving mangroves at the Rewas Jetty in the Raigad district in 1983. A large tract of mangroves (about 100 hectares) was then being destroyed for industrialisation by reclaiming this “wasteland”. ‘Save Mangroves’ campaign was then taken up by the Bombay Environmental Action Group, which filed various petitions in the Bombay High Court and the Supreme Court of India to protect this important and vulnerable ecosystem in our country. The Conservation Action Trust takes this legacy ahead and spearheads the mangrove conservation programme in Mumbai and the State of Maharashtra.