Little by little, India restores its lost mangroves

My excitement grew as we approached Muthupet, some 350 kms south of Chennai in Tamil Nadu. It was seven years after the devastating 2004 Indian Ocean tsunami, and I was visiting the region’s protected mangrove forests to do a story on their regeneration under the World Bank supported Emergency Tsunami Reconstruction Project (ETRP). 

As we boarded the Forest Department boat to reach the restoration area, I remember seeing a group of women wading across the shallow channel, their sarees hitched  neatly above their knees as they picked their way through the gently flowing waters. “They’re on their way home after planting mangrove saplings along recently-dug canals,” a uniformed forest guard told me. 

Although this was nearly a decade ago, a recent article on how a 54-year-old fisherman had helped restore the region’s mangroves, brought those memories flooding back. 

It wasn’t until the 2004 tsunami that mangroves emerged as one of the unlikely stars that could avert the worst impacts of such disasters.  When the tsunami’s gigantic waves crashed onto Tamil Nadu’s shores, just six hamlets, which still had mangroves ringing their coastline, escaped the fury of the sea. This was in stark contrast to the devastation faced by 11 nearby habitations that had lost this natural protection. 

"We saved the mangroves, and they saved our lives and property," said one fisherman. 

Today the world’s mangroves are threatened 

Mangroves play a vital ecological and protective role.   Found exclusively in the intertidal zones of rivers and estuaries, they help recycle nutrients, maintain the hydrological cycle, protect the coast from storm surges, and serve as nurseries for fish and other marine creatures of high ecological and economic value. 

They also house endangered wildlife like the Royal Bengal Tiger, fishing cats, otters and salt-water crocodiles. What’s more, they are powerhouses for carbon storage, sequestering four times more carbon than rainforests, with most of this carbon being stored in the soil beneath. 

Tamil Nadu alone has some 13 species of mangroves, while the Sunderbans in West Bengal are home to as many as 48 different varieties, all with different levels of salt tolerance.  

Although mangroves are a highly salt tolerant species, they need a regular influx of fresh water to survive.  However, the delicate balance of nature needed to maintain the mangroves’ highly specialized ecosystems remains only partially understood, even amongst disaster risk experts.

Today, the world’s mangroves face both natural and man-made challenges. 

Tamil Nadu, for instance, lost five mangrove species that could not withstand the higher soil salinity after the Cauvery river started arriving at its delta almost completely devoid of water, especially in summer. Even more worrying, the lost species offered greater resistance to the ingress of the sea. 

Moreover, the few stretches that remain are under severe pressure, especially from the rise of commercial shrimp farming. And many large patches receive no protection at all as they fall outside the Forest Department’s jurisdiction. Add to that changing climatic regimes, rising sea levels  and falling fresh-water flows, and their survival becomes even more difficult.

Restoration continues along India’s vulnerable east coast

In Muthupet, the World Bank supported Emergency Tsunami Reconstruction Project helped regenerate more than 2,000 hectares of mangroves along the most ideal sites  - adjoining existing stretches. Both salt-resistant species as well as those that reduced  soil salinity were planted to maintain the natural balance. 

Falling diversity was addressed by introducing ten new varieties sourced from areas which still retain rich mangrove patches, including Pichavaram on Tamil Nadu’s Cauvery Delta and Odisha further north. A species that was present 150 years ago was also revived.  

Once restored, these natural wonders played their protective role. When Tamil Nadu was battered by cyclone Gaja in 2018, Muthupet’s mangroves broke the velocity of the wind, saving the town from significant damage.

Other projects too have taken up restoration work. In 2014, after Cyclone Hudhud, the World Bank-supported Andhra Pradesh Disaster Recovery Project planted diverse species on 130 hectares and created a nursery of about 100,000 saplings. 

“The ground conditions are very difficult, the species diversity is low, the conditions hyper saline, and it is difficult to find people who know how to make channels and plant mangroves,” said Nandani Salaria of the Indian Forest Service who oversaw the restoration work. “What drives us, however, is the idea of regenerating our mangroves and restoring species diversity.” 

Indeed, restoring India’s mangroves is the way forward for building coastal resilience. Disaster risk management projects now need to mainstream them.