Pichavaram - the great mangrove forest of Tamil Nadu

Few people know (or care) that this favourite locale of filmmakers is a spectacular mangrove ecosystem throbbing with life

The mangrove forests of Pichavaram comprise an intriguing ecosystem

Tickets in hand, negotiations with the boatman closed, we should have been on the boat, headed for our first visit to a mangrove ecosystem. But all we could do was to gaze longingly at the dense green clumps across a vast expanse of the lagoon. The boat that was to carry us there was moored to the shore covered in blue tarpaulin. A sudden squall was depositing even more rain on the already soaked and overflowing coastline of southern Tamil Nadu and we were right in the centre of it all – at the northern edge of the Cauvery delta. 

A sudden squall threatened to drown out our much-awaited trip

Pichavaram, one of only two mangrove ecosystems located in Tamil Nadu, is approximately 75 km south of Pondicherry and 15 km from the temple town of Chidambaram. We had reached Pichavaram in the afternoon after a very enriching visit to the great living Chola temple. To be fair, the day had been fairly dry but now that we had planned to be on open water for the next four hours, it had started pouring.

Our entry into the mangroves began with the boatman negotiating one of the tamer channels

The Cauvery delta is formed when the river breaks up into multiple distributaries after Srirangam island. The northernmost distributary Coleroon (or Killidam) meets the sea near Pichavaram (the other river that drains this area is Vellar and the wetland is referred to as Vellar-Pichavaram-Coleroon wetland). The other mangrove patch is at Muthupet, which happens to be at the southernmost point of the Cauvery delta; the distance between the two is 180 km. Muthupet has a large lagoon where six distributaries discharge their waters. These mangroves are characterized by a long dry season (February to September) and high salinity.

Inside the mangroves

The shower stopped as suddenly as it had begun. We were off in a jiffy, the boatman rowing slowly and steadily across to the mangroves. Clouds streamed in from the ocean, promising more rain, but we pretended not to care. Pichavaram has almost 4,000 rivulets of varying length and width with mangroves on either side. As we entered the first, not more than six feet across, we saw the mangroves up close. They seem to grow out of water (there is not a patch of ground visible anywhere) almost like a floating forest.

The canopy weaves a tangled web, and not always a friendly one

The boatman was accomplished at clearing our way

As the boat negotiated the first turn, to our utter amazement and delight we entered a long and narrow rivulet completely wrapped in mangroves. It was like entering a green tunnel – the boatman had to row by moving the low, tangled mangrove branches out of the way. The banks of the rivulet were covered with mangrove roots reaching into the water – hundreds for every clump. The sky was swallowed up completely by the arches of these low trees and all we could see was the narrow rivulet and a vast impenetrable forest growing out of turbid water. The world had dissolved into an expanse of brown and red stilt roots (and all the shades in between) and the luxuriant green foliage of the mangroves, upon which streaks of sunlight created an impressionist canvas of rust, brown, olive, jade, lime-green and emerald.

A maze of stilt roots

In the eerie silence, as we negotiated one tunnel after another, crabs lit up the scene. They were everywhere – climbing up from the water’s edge, clinging to the trunks, hanging on to the canopy and perched in silence on overarching branches. A myriad species of crabs inhabit the forest and it was unfortunate that we knew so little about them. Soon enough we entered one of the wider channels. It was almost 100 feet across, like highways connecting the islands of mangroves. Forest towered on either side, dense and glistening in the evening sun.

The low boughs were the province of a myriad species of crabs

The east coast wetlands starting from the Sundarbans right down to Pichavaram (and Muthupet) receive a major infusion of fresh water from the rivers either throughout the year (the snow-fed Ganga and Brahmaputra) or during the northeast monsoon (Krishna, Godavari and Cauvery). Salinity levels vary through the season in proportion to the fresh water discharge but the trend is towards an increase in salinity as we move down the coast. So, while the Sundarbans have the least salinity (and the shortest dry season), the mangrove wetlands of the Cauvery delta have the maximum salinity levels and the longest dry season. Salinity (or the absence of freshwater intake) has an observed impact on biomass and species diversity. The Sunderbans and Mahanadi mangroves have 26 recorded mangrove species (out of the 33 found in India, 51 in South Asia and 68 worldwide), and high biomass due to tall low-salinity tolerant trees. But the mangrove species diversity drops to 17 for Godavari, 12 for Krishna and finally 11 for Cauvery. 

The sea-water dominated mangroves of Gujarat (with almost no fresh water infusion) have a species diversity of just eight. Further, the dominant species in all the high salinity mangroves -- those of the rivers Cauvery and Krishna and in Gujarat -- is Avicennia marina, an extremely saline water-tolerant species.

It has been observed that except in Andaman and Nicobar Islands, where the mangroves along tidal creeks, lagoons and bays are extremely diverse, those of the east coast are gradually being dominated by high salt-tolerant species like Avicennia marina due to changes in quantity and periodicity of fresh water. It has been found that the vegetation of Pichavaram and Muthupet wetlands used to be more diverse in the beginning of the 20th century but since the freshwater inflow was severely curtailed by the numerous dams and canals upstream on the Cauvery, Avicennia marina became dominant.

Mangroves receive an infusion of river water during the monsoon

We spent almost three hours in this verdant forest. It was a strangely hypnotic world. The dense forest growing out of the water, trees on stilts, and meditating crabs perched where we expected birds, puzzled our senses. But it was a real world, a shrinking and vulnerable patch of forest, and probably the last remnant of the much vaster mangrove forests that occupied the Cauvery Delta.

A strangely hypnotic world

Note:

Mangrove wetlands in India are in most cases the gift of east-flowing rivers. Other than the geological fact that India has no major west-flowing rivers, the east coast is gentler and wider and thus aids major rivers in creating large deltas and an accompanying network of tidal creeks and canals, and brackish lagoons where the mangroves thrive.

The major mangroves patches in India are Sunderbans (Ganga-Brahmaputra), Mahanadi (Mahanadi, Brahmini and Baitarani – the famous Bhitarkanika wetland), Godavari (the Gautami-Godavari system creates the Coringa wetland), Krishna (three islands located between Gollamattapaya and Nadimeru distributaries, and the Krishna river) and Cauvery (Pichavaram and Muthupet). The river dominated (tide-dominated in the case of the Sunderbans) mangroves of the east coast comprise approx 57 percent of India’s mangroves.

The west coast mangroves, all of which are in Gujarat (Gulf of Kutch and the Gulf of Khambat), comprise about 23 percent and those of Andaman and Nicobar Islands make up the remaining 20 percent. There are no statistically significant mangroves outside these five states (Andhra Pradesh, Tamil Nadu, Odisha, West Bengal and Gujarat) and Andaman and Nicobar islands, though small patches exist along the coasts of Kerala, Karnataka, Maharashtra and Goa.

We saw very few birds inside the forests but for the Striated Heron or the Mangrove Heron

The Gujarat mangroves are of a very different type. They are “sea mangroves” since they receive almost no freshwater from inland rivers during the year. These are classified as “drowned-valley type mangroves”.

Text and photographs by Sahastrarashmi
Additional photographs by Bijoy Venugopal


References: 


V Selvam, Environmental Classification of Mangrove Wetlands of India [PDF]

Life and death in Kaliveli's salt pans

Driving between Chennai and Pondicherry, approximately 30 km before you reach the former French enclave, you cannot but notice a small inlet channel from the sea passing below a narrow bridge and then expanding into a vast lake stretching all the way to the western horizon. This is Kaliveli, the second largest natural lake in southern India (after Pulicat Lake in Andhra Pradesh) and unfortunately among the most neglected wetland ecosystems of the eastern coast.

Kaliveli is connected to the sea by the Yedayanthittu estuary from which there is a considerable intake of sea water. Along its large catchment area are numerous tanks and channels that pump in fresh water especially during the monsoon (October to December) and hence this wetland has a salinity gradient useful for a large array of waterbirds, amphibians, reptiles, molluscs and fishes. Estimates of the exact size of the wetland vary (a substantial portion of the lake is a seasonal wetland) and a documentary film by FERAL puts it as 70 sq km. Kaliveli is classified as an Important Bird Area (IBA) and is an important wintering location and stopover point for winter migrants. Wildlife biologist K S Gopi Sundar once counted over 300 White Storks (Ciconia ciconia) at Kaliveli.

A large area of the wetland, especially the eastern edge along the East Coast Road, has been converted to salt pans. Initially, while driving past the pans on my way to Mahabalipuram and beyond, I used to be fascinated by the sculptural beauty of the salt heaps stretching all the way to the horizon, snow-white pyramids neatly placed in a vast chequered landscape of neatly squared salt pans. It was sheer photogenic geometry. Soon I was to become familiar with their more disturbing aspect, ecologically speaking.

A gravid female Fan-throated Lizard

Spider carrying an egg sac

Remains of a dead tortoise

The body of a snake, consumed by the brine

A crab seems very much at home in the salt pans

In July last year, Gopi and Swati were in Pondicherry and we went over to Kaliveli. As we entered the salt pans we noticed the absolute absence of birds. Barring a few Black-winged Stilts before the bund, we saw no no birds amid the rows of salt pans. Except for some Fan Throated Lizards (Sitana ponticeriana) – among them a number of gravid females -- and some crabs peering out of their burrows along the water channels, everything we saw was dead. There were dead fish in the water channels (closer to concentrated brine than water) no doubt trapped in the channels during the high tide, a dead tortoise, dead snake, dead dragonflies and thousands of shells of dead mollusks. Almost every form of life which had ventured into the salt pans had been quickly snuffed out by the brine. As we walked through the pans towards the edge of the lake trying to get a closer view of the Greater Flamingos that we had seen as pink specks from the road, we came across a remnant mangrove patch along the border of the lake, trying to spread outwards towards the pans but brutally kept in check by human intervention. The entire area of the salt pans was once a mangrove forest, and was later chopped down for the salt industry, thus depriving the east coast of a rich mangrove and estuarine ecosystem that would have rivaled those of Pichavaram, nearly 100 km south.

The salt pans have extended the area of the brackish water further into the lake and have thus alerted the salinity gradient of the lake. The ground water is now so brackish that some salt pans are no longer dependent on the intake from the sea; they simply pump the brine up from the ground.

Painted Storks and Openbill Storks forage beyond the salt pans while the brackish shallows beyond the mangroves play host to Greater Flamingos

A last stand of mangroves

Mangrove forests like these once covered the east coast

It has taken remarkable official apathy to destroy a rich natural wetland ecosystem (Kaliveli continues to be without legal protection). Not even “tourist infatuated” bureaucratic machinery has been able to see the potential of a well-protected, incredibly rich birding area so close to a tourist hub.

Text and photographs by Sahastrarashmi


Further reading:
A manual on Kaliveli (PDF) from the Foundation for Ecological Research, Advocacy and Learning (FERAL)

God's own garbage

I was brought up to be religious. When I could think for myself, I changed my view. But temples located amid forests still held a fascination for me - it was the journey, rather than the destination, that appealed to me most. 


It's been a long time since I have visited any temple in the capacity of a pilgrim. But, yes, temples do form part of my itinerary whenever I travel. On a travel writing assignment in 2008, I was required to visit the famous Arulmigu Dandayudhapani Swami Devasthanam at Palani. It's an ancient and venerable temple and I suppose it must have remained harmonious with its immediate environment, as temples once used to. 


I had visited Palani as a child (a memory intertwined with one of my first toothache) and I remembered it to be a far prettier place than it is now. Of course, the devout may differ with me on that. Then, the climb of 693 steps to the sanctum was pleasanter, with shady trees to help break your journey in comfort. 


And there was no plastic.


These pictures, taken two years ago, show a different Palani - one that has unfortunately replaced that old childhood idyll in my memory. I doubt it would have changed if you happen to visit it now. If it has, for the better, do let me know.

On one side, the view from the summit

On the other, a mountain of plastic and garbage

En route, a fervent plea falls on deaf ears (or illiterate eyes)