Category: Science of the Seas

In response to my previous post, Indumathi Manivannan Nambi, an eminent environmental scientist from IIT-Madras, had flagged a very important issue – that of plastic trash and its impact on fish. “I also read that fishermen dispose their [plastic] nets in the ocean. Can we try to bring awareness about the impact of this?” she asked.

I confronted Palayam anna with Dr. Nambi’s question. Palayam’s response to her query suggested that awareness may not be the problem. “Kadalukku onnuna engalukku theriyaama irukkuma-naa? Naanga kadalodaiye thaane irukkom; Engalukku thaane mudho theriya varum.” (We are always with the sea. We’re the first to know what’s happening to it. Can you get that, brother?)

Exactly a year ago, maybe a day or two less than a year ago, the fisheries department dropped about 200 artificial reef units – interconnected rings of concrete – into the sea off Urur Kuppam. “At 11.5 fathoms,” recalls Palayam anna. Reefs, even artificial ones, are excellent habitat and refuge for sea life. They provide a base for vegetation and for coral to colonise, and a place for young fish to hide.

A few months later, I enquired about the reef. Palayam anna was resentful. The reef has been ruined, he said. Careless fishers had let their nets drift onto the reef. The nets had snagged on the reef. Fish that got trapped in the nets rotted away, turning the reef from a refuge for fish into a fetid, repulsive graveyard. Our fishers were to blame, he said. Some of them are driven by greed, and others are plain stupid, anna explained.

To understand Palayam’s anguish, one needs an idea of how a fisher makes sense of the seas. The ocean’s bottom is the basis of a fisher’s mind-map of the seas. He navigates and identifies fishing grounds based on the depth and the nature of the sea floor. Sandy areas are called tharai and are least productive; muddy patches are seru or cheru, and rocks or reefs are paar/paaru or kal/kallu. The latter two are productive and sought-after fishing grounds. Every seru and paaru has a name – thazhancheru, mecheru, naducheru, thalappu kallu, kinathu kallu. “Unga bank accountukku number illaiya? Athey maathiri thaan. (Don’t you have a unique number for your bank account. This is just like that),” Palayam says.

Palayam anna, and just about any fisher in this region’s fishing villages will be able to rattle off the names and locations of the seru and paaru spread in the local seas. It is committed to memory. More about this in another post. This one, I remind myself, is about abandoned or discarded fishing nets littering the seas.

Setting nets near reefs is tricky. You want to be close enough to net the fish that hang out near the reef. But you need to be far enough to avoid snagging your net on the reef. That would be bad for the net and the reef. The currents add another complicating dimension. “kadal olni kudukkuthunu theriyidhu illai? pinna 20-25 point melappoi valaiya kattanum. (When the olni current (east to west current) is evident, you should go 20-25 (GPS) points further out (further east) and set your net.),” he says. Greedy or inexperienced fishers underestimate the olni. Then everybody pays for this idiot’s mistake, as the current drags the net westwards and snags it on the reef.

As luck would have it, a day after Dr. Nambi brought up her question, we spotted a knotted bundle of net washed up by the tide. Palayam pointed it out to me.

According to The Guardian article referred to in Dr. Nambi’s query, 640,000 tonnes of plastic nets, lines, crab pots etc were added to the world’s seas every year.

This is a small fraction (8%) of the total quantum of plastics entering the oceans. But it is not insignificant. Discarded nets float around snagging or harming all kinds of sea animals – turtles, dolphins, manta rays, even whales.

But nets cost money. People don’t just discard good nets at sea. “Then what explains the nets littering the sea?” I asked. A bulk of the fishing gear, especially the industrial gillnets and purse-seine nets some several tens of kilometres long, littering the world’s seas are from industrial and trawl fisheries. Even without the abandoned or discarded nets that float around like long walls of death, these fisheries are destructive by their very nature and scale. They take more than they need and extract far more than the seas can replace. Plastics are not the problem here. The exploitative capitalist, industrial fisheries model is.

Artisanal fishers like Palayam and the others from Urur Kuppam too contribute to the problem of ocean plastics. But in a far smaller way. Sometimes the nets that they set are severed by the propellers of other boats, trawlers or ships. Inexperienced fishers may steer their boats into their own nets and snag them on their propeller blades. “When this happens, it is a major nuisance,” Palayam says. We have to stop fishing. The propeller shaft is brought onboard, and the frustrating, time-devouring task of unravelling the wound-up net and punnu (nylon rope stringing the net) begins. Often, frustrated by this exercise, fishers may just chuck the extricated knotted bundle overboard. “In that moment of stress, it doesn’t occur to them to retain the trashed net onboard and dispose of it on land,” he says. That can be changed with education and incentives, Palayam thinks.

But he is unforgiving with fishers, like the ones that snagged the nets on Urur’s artificial reef, who give in to their greed, and knowingly risk their nets and the reef by setting their nets close to the paaru. “Kadal nalla irukanumna, oorla othumai venum. ooru kattu potta mathikanum. (If the seas are to remain healthy, the village has to be united; the fishers have to subject themselves to the norms imposed by the village),” he explains. He points to the southern districts where artificial reefs dropped decades ago are flourishing habitats. “There, the fishers respect the fishing norms, and the rights of others to fish. They don’t endanger the commons, and protect the reefs like we protect banks,” he said, once again referring to the sea as a “bank” – or a place with a lot of money.

There is one reef called Thalapukallu at 15.5 fathoms that Palayam refers to as Reserve Bank. “Eppo ponalum panam edukalam. ATM mathiri. (You can make money any time over there. Like an ATM.)”

The bundle of nets in the video below is a twisted collection of different kinds of nets. Usually, the nets that get cut by propellers tend to be floating nets cast for pelagic fish (fish that swim in the surface or sub-surface) like the prized kola or flying fish. Palayam explains that what you see in the video is an inextricably intertwined bundle of different bottom-set nets (tharai valai) from different fishing expeditions that have somehow found each other. The two of us lugged the bundle and moved it well beyond the high tide’s reach.

Cleaning the seas is a difficult task. But if we want more bang for the buck, we could focus on doing two things, he says.

Far into the sea, when we sail in search of the kola, we cross this visible line in the sea running roughly parallel to the horizon. Edaappu (the interface) is what we call the regions separated by the line. The line itself we call Neettil. To one side of the Neettil, towards land, is kalvaadu (turbid water) and on the seaward side is thelivu thanni (clear water) that is home to the flying fish. The Neettil is marked as a line of trash of all kinds – cans, bottles, lighters, buoys, nets. Everything that gets thrown off these big ships will end up bobbing along the Neettil. In earlier days before plastic became popular, white people used metal cans of all kinds in their ships. They would throw this overboard. Sometimes, if we are returning with an empty net, we would clean-up a stretch along the Neettil and bring the metal scrap home to sell to the scrap merchant and earn a few hundreds. But now, the trash is all plastic. No point bringing it back.” If a cleaning ship were to focus on sucking up the trash just from the Neettil, that could be significant.

The second suggestion is to focus on the reefs near shore. If divers can get to it, and remove it, that would be a big help. But this would be a wasted effort unless fishers commit to protect the reefs by setting their nets well away from the jagged edges of the reef. To help fishers do that, big, visible, well-lit buoys must be anchored near the reef.

The commons – like the oceans – can be preserved only if its users commit to following some basic norms. Among fishers, these norms are enforced as taboos and dos and don’ts. But with increasing urbanisation, atomisation of the fisher society, and the pursuit of private profit community bonds and the strength of these fishing norms have eroded.

Awareness, Palayam says, won’t make a big difference. “It’s not worth the effort,” he says. “The community needs to be brought together, and the individual must realise that his fate is linked to his brother’s.” To paraphrase Palayam, it is not so much that the fishers lack common sense. Rather what is increasingly in short supply is a sense of the commons.

The sea seemed joyous today, as if at the prospect of meeting its friend, the river. The malodorous, deathly condition of the Adyar seemed not to have affected the sea’s enthusiasm. The estuary was open. The massive fish kill we feared had been averted, saved by the sea. The rank, putrid smell was thankfully gone. “It is the power of salt,” said Palayam Anna, referring to the healing effect that tidal flushing had on the health of the river. He does this frequently. Refers to the healing powers of sea salt, I mean.

Last night, the earth mover appears to have fulfilled its karmic duty. A 50 metre gash had been cut through the sand bar separating the two friends. Seawater surged through the opening and flooded the river.

To the ever hopeful fisherman, there’s a lot more to the sea than just salt water. “There’s a lot of fish in this river. You don’t see them. See how much they caught these last few days. Would anybody have known there was so much fish to catch in this river? It’s all thanks to the sea. Even now, our eyes only see the seawater washing in. But every wave brings with it fish of all kinds – oodan, pachakutty, madavai, kezhangan, thumbili,” says Mani, an Urur Kuppam fisher who is here every morning, most days with his hand-cast net and sometimes just to stare out at sea. Fishing is his early morning job. He is close to retiring from his day-job in Metrowater. For now, though, he is a fisherman moonlighting as a fisherman. That’s quite normal in fishing villages. One foot may be in an IT company, a printing press or a government office. The other is always in the river or the sea.

The tide was already high. The sea was rough and powered by a strong kachan karsalla (a current from the south). Angular waves struck the shore from the southeast in a process that fishers call kuthi vangarathu (dig/lunge and withdraw). Every strike dug at the base of the mound of sand on the northern bank of the estuary, causing a mini sandslide that the backwash swept back and distributed across the freshly excavated channel. The kachan had begun its job of closing down the freshly opened river. With every passing day, the sea would bring in sand to narrow the estuary even as it pushes the opening northwards. In a week, the river mouth would be narrowed to a shallow thin dribble about ten boat-lengths north of where it is today. In 10 days, it would be sealed shut. Standing at the southern bank, I could see Palayam Anna’s explanation of the phenomenon of erosion in action.

This morning, only one boat, Kumar’s boat, had ventured out. He must be setting a kadama valai – squid net. Squid and octopus are caught using bottom set nets. They’ll go to the fishing ground at 10-11 fathoms, Palayam said. If they return with some catch, others will go. No point everyone wasting diesel.

The air and Palayam’s manner are thick with a sense of expectation. That, he said, is usual for the third week of the tamil month of Aadi. Yesterday, August 3 and the 18th day of the month of Aadi, was the auspicious tamil festival day of “aadi perukku.” Celebrated by tamils across the world, this day is a tribute to water – the basis of all life. In Tamil Nadu, this also signals a time when the monsoons in the ghats spill over and flow right down the coastal plains to meet the sea. In a good year, Cauvery will have enough water to run right through to the tail-end coastal districts of Thanjavur, Nagapattinam, Cuddalore, Thiruvarur and Pudukottai. For the delta farmers, aadi perukku is a joyous occasion; it signals a healthy planting season.

Fishers too look forward to the days after perukku with great expectation and and even greater nervousness. If sufficient waters are released in the Cauvery, the surplus is diverted at the Grand Anicut into the Kollidam. When these nutrient rich waters are disgorged into the Bay, it gives birth to a marine phenomenon called “vanda thanni” (silt-laden waters). This is the equivalent of a single-day harvest season, a bounty, a lottery.

Telltale signs of vanda thanni’s arrival are many. “When we’re at midsea, we see clumps of long leaf-like river weed flowing north with the current. We call that Kollidathu Paasi (river weed from Kollidam),” Palayam says. “Then we know Vanda thanni is coming.”

Vanda thanni requires the convergence of three phenomena, explains Palayam – a copious outflow from the Cauvery and Kollidam; a strong kachan karsallu (south-north current), and a strong olni push where the deep sea churns upward and landward bringing ice-cold waters from the deep to add to the turbid nearshore flow.

When the Olni happens, which is usual for this time of the year, it clears up the sea right up to the nearshore. The mid and deepsea turns a clear sea-blue, while the nearshore runs turbid.

And then there is the temperature. “Thannikulla kai utta iceland-aa irukkum,” Palayam explains. “The water is ice-cold to the touch, like Iceland.” If that’s how cold it is near shore, imagine how cold it will be in deeper waters. That is why the fish – even deep water fish – escape. They seek out the less cold and turbid nearshore waters to lose themselves in the opaque silt-laden waters. When this happens, it is a bonanza for fishers. Now, with mobile phones, fishers get word of vanda thanni’s arrival well in advance. If the vanda thanni is seen near Kalpakkam, we get to know immediately; we get our boats and gear ready. When the current hits us, it is a like a river of fish swimming north – all kinds of tharai meen (bottom fish) – kaala, sura, panna, kadamba era, korukkai/koduva. Fish that we’d go searching for deep into the sea will be making our nets heavy right next to the shore. If we’re hardworking, have a good team and wise counsel, the sky’s the limit. The only limiting factor is our strength and the speed at which we can empty our nets and return to fish.

“Adi vellam, thedi paayumnu solluvanga (The aadi waters will seek you out, it is said). With luck, if you land a school of kadamba era (tiger prawn) each boat can earn lakhs in just one day.”

Last year, the vanda thanni was weak. But in 2019, it arrived with a bang and with lights, albeit a bit delayed. The beaches from Kovalam to Besant Nagar were alight with the blue glow of bioluminescence – a feature that sometimes accompanies vanda thanni. See Palayam Anna’s explanation of bioluminescence and vanda thanni here.

That day, his boat hauled in Rs. 80,000 worth of fish in four trips. “We held the record for our village that day. Other boats made 60,000, 50,000 and all. This much is a given. Era kadacha bonus (If we land prawns, that’s a bonus). Then the income can go up in lakhs,” Palayam says. “The sea is nature. Nature is god. It is whimsical. But if you have faith in it, it will take care of you. If not today, then another day. You will be given. Kadal thozhilla vex aagakoodathu. (With sea trade, there is no room for cynicism.) You have to work, work hard and keep working and waiting for those few days when the sea is in a giving mood.”

Coming from an artisanal fisher, this advice highlights how internalised his understanding of nature is – that vagary is the very nature of nature. Contrast that with the engineering mindset of modern corporate fisheries that views such dealings with chance as primitive. The quest of modern engineering to eliminate chance taunts nature, and invites doom. Where the artisan operates with humility, the other exudes a hubris exhibited by fools that venture where wise men fear to tread.

Let’s hope this vanda thanni brings a happy new year to all our fisher friends and puts tasty fish on our tables.

“Unless saved by the sea, at this rate, expect a significant fish kill in Adyar in the next few days,” Palayam anna muttered to himself.

We only wake up after disaster strikes, and slip back into slumber soon after. As Chennai-ites, we know that only too well. Fish kills and foaming seas are routine occurrences. But our friends in the media never fail to appear surprised every time we hear news of dead fish in the Adyar. That shouldn’t be news. A year without a fish kill is newsworthy.

Every annual fish kill brings up the same trite questions of what could be the cause. It’s not as though the city has stopped shitting in the river that the cause would be any different this summer.

This last week has been a build-up for the big kill. Since the last full moon, the artificially opened river mouth along the southern bank steadily shrank as it crept northwards pushed by the thendi thanni (southerly currents). Three days ago, the mouth was sealed off and for at least two days, the fish trapped behind the closed river mouth have been stewing in a still, shallow cesspool.

This morning, Palayam Anna and I met one fisherman who netted 200 kg of oxygen-starved fish from the placid shit-waters of the blocked estuary yesterday. Today, the river’s edge was littered with dead and dying fish – not yet in numbers sufficient to rouse us from slumber.

A JCB earthmover has been idly parked near the Broken Bridge for three days now. Palayam and I discussed it, but we don’t know what it’s waiting for. The isthmus separating the river from the sea waxes and wanes with the moon’s cycle.

Perhaps the JCB is waiting for the patch separating the river from the sea to narrow to a thin sliver by the next new moon (August 8). There would be less work to be done excavating a channel for the river’s exit.

By that time, though, the conditions may ripen for a newsworthy fish kill. Until then, let’s return to slumber.