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Story Publication logo March 25, 2023

The Rise and Fall of a Commercial Seaweed — and a Community’s Fortunes With It


Two seaweed farmers at work

Nature-based solutions can impact local biodiversity. This project highlights the dangers of...


Kappaphycus alvarezii. Image by Aparna Ganesan. India, 2023.

Rameswaram, Tamil Nadu—On the southern tip of the Indian subcontinent, Pamban island is straddled by India and Sri Lanka. On the west, a single railway line and an asphalt bridge run parallel to the turquoise water, connecting the island with mainland India. And on the east, a chain of natural limestone ridges, often known as Adam’s bridge or Rama Setu, reaches out to Sri Lanka.

Kuppaswamy’s village – Cinnapalam – lies just a few kilometres from where the railway line ends. Kuppaswamy (52) has been fishing since he was a teenager. Like the other traditional small-scale fishermen on this island, part of his job is to navigate the waters around Pamban and the other small islands which surround it. The fishermen would ride their plank-like canoe, locally known as vathais and vallams, and use nets to catch fish, which were once available in abundance. 

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Rameswaram is straddled by India and Sri Lanka. Image courtesy of Google Maps.

All his life, Kuppaswamy has been venturing into the sea. Over the years, he noticed the degradation of corals because of human interference. He remembers, three decades ago, the corals were mined for limestone, for use as a construction material. And then roughly 20 years ago, came a pasi, or seaweed in Tamil.

“It was the seaweed collectors who first noticed it,” Kuppaswamy recollects. It looked rubber-like, a thick grapevine floating on the water, only without the grapes, and brownish with hues of green. In a matter of days, the community realised that this new entity was hitchhiking on the corals, smothering and killing them by blocking the sunlight. 

The seaweed Kuppaswamy is referring to is called Kappaphycus alvarezii, which was brought to India from the Philippines for experimental purposes during the 1980s by a government agency, the Centre for Salt and Marine Chemicals Research Institute (CSMCRI). 

It did not take long for the seaweed to jump from the experimental farms to commercial ones. With the help of CSMCRI, PepsiCo began commercially farming the seaweed in the coastal areas of Tamil Nadu in the early 2000s. Kappaphycus alvarezii is an important source of carrageenans – which are used in a variety of foods, such as a stabilising agent in dairy products. Industrial products like chocolates, ice creams, packaged food, toothpaste and even medicines, to name a few, utilise this jelly-like agent.

It gave the locals a new form of employment, so traditional seaweed farmers like Mutha, who stays about 12 km away from Kuppaswamy’s village, grabbed the opportunity. Its commercial viability allowed her to provide for her family and send her son to school and then college.

But then in 2014, the seaweed stopped growing. 

The companies who procure seaweed from farmers like Mutha want new fragments of Kappaphycus to be introduced so that the industry will revitalise. But there is also potential that new varieties will damage the already threatened corals in the Gulf of Mannar Biosphere Reserve, which is recognised by UNESCO as a region with rich marine biodiversity.

Though PepsiCo introduced the seaweed to the locals, it exited the business around 2008. An ex-PepsiCo employee, Abhiram Seth, took over the business by setting up a company called Aquagri. But regardless, the locals continue to call Kappaphycus “Pepsi pasi”.

The commercial cultivation of Pepsi pasi started around the reef areas in 2005 and neared its peak in 2007. Mutha, the seaweed farmer, remembers it would grow as tall as her “only in a few weeks”. Its production also grew in leaps: from a 5 cm piece to 21 dry tonnes in 2001 to 1,490 dry tonnes in 2013.

But right from the beginning, there were concerns about spillover. In 2007, “bio-invasion” was first observed in branching corals of the Acropora genus near the Krusadai island, according to the Gulf of Mannar Biosphere Reserve Trust’s documents. Within 24 months, reef areas of over 1.2 square km and over 500 branching and massive coral colonies in Krusadai island were destroyed, the documents say.

Krusadai and other nearby islands have long been used as traditional fishing hotspots by Kuppaswamy and other residents of Cinnapalam. Krusadai is one of 21 islands that form the 560 sq km area of the Gulf of Mannar National Park, one of India’s four major coral reef areas. When the region was designated as a national park in 1986, Kuppaswamy and others lost many of their rights to freely access the hotspots. It was later declared the first Marine Biosphere Reserve of India in 1989.

Around 18 years later, when Kuppaswamy and other farmers found the pasi growing on and destroying the corals, they were perplexed. “The government asked us to stay away from the corals in the region, but then allowed a seaweed which was damaging the corals to be grown,” Kuppaswamy says.

All across the planet, corals are under threat due to anthropogenic stressors, including habitat destruction, pollution, sedimentation, overfishing and climate change. It is estimated that over 65% of the existing coral reefs in the Gulf of Mannar region are dead – primarily due to human interference. 

Coral reefs are some of the most diverse ecosystems on Earth and support more species per unit area than any other marine environment. Traditional fishermen like Kuppaswamy know the role corals play in sustaining fish populations. “No corals might mean no fish,” he says.

So, when Kuppaswamy and other farmers witnessed Kappaphycus growing on the corals, they approached the forest department with their concerns in 2007. A team of experts was sent to the location to estimate the danger due to the species. Naveen Namboothri, a marine biologist and the founder of the NGO Dakshin Foundation, was part of the team. “We witnessed the growth of Kappaphycus on the bodies of both dead and living corals,” he says. 

Soon enough, drives to eradicate the colonies of seaweed from the surface of corals began. “Many from our village were paid to clear off the seaweed,” says Kuppaswamy. Nambu, a septuagenarian seaweed farmer, participated in these drives. He recalls, “The pasi made the corals weak. When we pulled out the weeds (manually), it broke the corals and the corals shred like powder.”

Even as Kappaphycus was beginning to be seen as a problematic species, it had already established itself as commercially viable. The locals and the industries had tasted the success that the foreign seaweed brought. 

In the late 2000s, the National Biodiversity Authority (NBA), a Government of India body that works on the issues of conservation, sustainable use of biological resources and fair and equitable sharing of benefits, made an agreement with PepsiCo on access and benefit sharing (ABS). 

ABS is a component under the UN Convention on Biological Diversity (CBD) that ensures fair and equitable sharing of benefits arising from the use of genetic resources for the welfare of the local biodiversity.

As part of the agreement, PepsiCo exported 2000 MT of seaweed to Malaysia, the Philippines and Indonesia, for which the NBA received Rs 39 lakh. Besides, almost 90% of the monetary benefits of the NBA came from this single case and source.

While the CBD aims at reversing the rate of biodiversity loss, in this case, it was utilised to promote a non-native species in one of the most biodiverse regions of the world. The focus of the agreement shifted from the significance of genetic resources and biodiversity to the commodification of resources. 

When this approval took place, the state of Tamil Nadu did not have any local Biodiversity Board to utilise the money for the welfare of the local people. Three years later, in 2010 the NBA admitted that the money received from Pepsi was “yet to be ploughed back to the benefit claimers”. Now, the NBA says that the money was used for the welfare of the people – but the locals are unaware of any measures that were taken. 

The NBA has now stopped providing access permits, because of the ongoing controversy of Kappaphycus, as per an official who does not want to be named. Along with NBA, the Gulf of Mannar Biosphere Reserve Trust maintains that the Environmental Impact Assessment that was conducted before the Kappaphycus was released for commercial production was not sufficient, which led to the spill out of the seaweed from the region.

But CSMCRI, which helped in the technology transfer, continues to claim that the seaweed is not invasive and does not cause any harm to the ecosystem. In an email, a scientist from CSMCRI responded, “This particular species — Kappaphycus alvarezii has not been reported to be invasive from any part of the world.” CSMCRI refers to the species as native and distinguishes it from the Kappaphycus spp. However, Kappaphycus spp. and similar species, including Kappaphycus alvarezii, are marked red in the Global Invasive Species Database. 

A scientist at CSMCRI said, “There is not enough evidence to prove that the Kappaphycus is harmful [to] the ecosystem.” 

Another government agency, the National Academy of Agricultural Sciences, in a 2003 document also marked Kappaphycus “ecologically safe”. It was introduced to Indian waters more than ten years ago and was “domesticated”, the document says.

But, according to another researcher, S. Sandilyan, a former fellow on invasive alien species at the Centre for Biodiversity Policy and Law, there is not enough evidence to prove that it’s safe either. Similar to other species like water hyacinth, it can form colonies from a few fragments, he says.

Women from Pamban island collect Kappaphycus alvarezii. Image by Aparna Ganesan. India, 2023.

The organisations and researchers who reported the invasion of Kappaphycus have become inactive. No new intensive independent research has come out in years to definitively categorise Kappaphycus as harmful or otherwise.

According to Seth, the CEO of Aquagri, the largest company now involved in Kappaphycus, the industry has crashed over the past decade. He says in 2014, around 2,000 farmers were involved in Kappaphycus collection, which has dropped to 200-300 farmers currently. During 2013-2014, the production of Kappaphycus dropped abruptly by 90%. Scientists speculate it could be due to “extreme heat” and “losing vigour of the germplasm”.

The scientists at CSMCRI are confident that bringing a new fragment of Kappaphycus can boost production again. Jeffery Wright, an associate professor at the University of Tasmania and an expert in seaweed biology and ecology, also agrees. “Bringing a new fragment may increase the genetic variability and fix the problem.” However, he warns, the authorities need to decide what’s more important: “To save the ecology or economy?”

Wright says it is not easy to identify or estimate the invasive potential of a seaweed “with the history of a few decades”. He says, “It may take up to 50 years for a non-native invasive species to actually show its properties. And sometimes even more.”

Namboothri, the marine biologist, says even if Kappaphycus is not yet considered an invasive species, its spillover may be explained by the ‘enemy release hypothesis’. The idea is that non-native species are less impacted by “enemies” or other external factors that control native species in an ecosystem.

But Kappaphycus is not the only seaweed whose production has crashed. Amongst the 4,223 species of plants and animals in the Gulf of Mannar region are other species of commercial local seaweed, like Gelidiella Acerosa (marikozhundhu pasi), Gracilaria edulis (Agarophytes, Kanchi passi) and Sargassum spp (kattakorai), which have been used by the locals for years. Their growth has also declined recently.

Moreover, challenges such as climate change aid the spread and establishment of alien species, according to IUCN reports. From the past records, it’s already noted that the locals witnessed a decrease in the production of other local seaweeds when Kappaphycus was introduced in the region.

The UN’s Food and Agriculture Organisation notes that the sensitive and fragile ecosystem of coral reefs is little researched in India. For now, “the species, Kappaphycus, has found an economic and social significance in the region, but twisting scientific facts to promote it is not the way ahead,” warns Namboothri.

Kappaphycus alvarezii. Image by Aparna Ganesan. India, 2023.

In this tug-of-war between science and scientists, it’s the local seaweed farmers who have the most to lose. What began as an ‘experiment’ for the authorities became a viable livelihood option for the locals. For many, it has already become unviable, although a few still stick with it.

Until a few years ago, rafts of Kappaphycus would float on the water on the coastlines of Pamban island. Only a few survive now. Mutha is one of the few seaweed farmers still harvesting Kappaphycus. When she began collecting Pepsi pasi, it gave her a financial ability that she couldn’t have conceived. It was the seaweed business that helped Mutha, a single mother, run her household. She sent her only son to school and moved to a better house. But now, she can collect neither enough Kappaphycus nor Marikozhundhu, the commercial seaweed she harvested before Pepsi pasi was introduced. 

She leaves her house early in the morning and walks for an hour to reach the beach. She wears a long shirt to avoid getting bit by small insects, wraps her fingers in pieces of cloth to protect her fingers from getting blisters and puts on her goggles to spot seaweed that is swept to the beach. She spends five-six hours doing this everyday, and yet does not collect enough to make ends meet.

Mutha prepares to collect Kappaphycus alvarezii. Image by Aparna Ganesan. India, 2023.

Murugeshan, who proudly mentions that he was one of the first to collect Pepsi pasi in his village, has now completely left the business. He has locked up the gear he used to cultivate seaweed – ropes and nets – in a trunk. The pasi, which once helped him educate his kids and build a pucca house, is “not profitable anymore”, he says. He now runs a small general store that sells biscuits, soaps and other products. He also takes to the sea for fishing, but not in the traditional way. He has joined a trawler fleet. 

Aparna Ganesan helped with translations.


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