The Palk Bay waters, on which fishing communities depend for their livelihoods. Image Source: Sidharth.D. via Wikimedia Commons.
In Rameswaram, Tamil Nadu, 45-year-old R. Suganthi wades into the Palk Strait before dawn to check her seaweed lines. Her mother collected seaweed from the same stretch of coast before her. A seaweed farmer and self-help group trainer, she has worked in these waters for most of her life. The red seaweed Suganthi cultivates, Kappaphycus alvarezii, is processed into carrageenan, a thickening agent used in dairy products, pharmaceuticals and processed foods across the country.
India imports nearly all the carrageenan it consumes, despite having the coastline, climate and coastal communities needed to produce the raw material. Yet many women cultivating seaweed remain unaware of its value in the wider market. Field researchers in Rameswaram found that most women farmers did not know how much their harvest was worth or who eventually bought it. When Suganthi learned more about the market, she began selling directly to buyers, eliminating middlemen and increasing her income by 50%. Her experience highlights how access to market information can influence the returns women receive from their work.
Her story reflects two interconnected challenges along India's coast: the degradation of nearshore waters and the economic pressures facing fishing communities that depend on these ecosystems. Seaweed farming offers a potential response to both by creating livelihood opportunities while helping absorb dissolved nutrients from coastal waters.
Kappaphycus alvarezii the red seaweed that women in Palk Strai cultivate. Image Source: Md. Simul Bhuyan via Wikimedia Commons.
Along the Palk Bay coast, seaweed farming is largely carried out by women. They wade into shallow waters during low tide, attach small fragments of seaweed to ropes or nets and return later to harvest the mature fronds by hand. The activity requires relatively little equipment and does not necessarily involve a boat, making it accessible to coastal households with limited capital beyond the initial seed material.
Seaweed is among the fastest-growing organisms on Earth. Kappaphycus alvarezii, the species Suganthi cultivates, thrives in warm, shallow tropical waters and is harvested primarily for carrageenan, a natural binding and thickening agent. Carrageenan is used in products ranging from ice cream, infant formula and processed meats to pharmaceutical capsules and personal care products. Seaweed also has applications in biofuel research and as a natural fertiliser.
Global demand for carrageenan is increasing, creating opportunities for countries that can cultivate and process seaweed at scale. India already grows the raw material but continues to import most of the processed product it consumes.
Beyond its commercial value, seaweed absorbs dissolved nutrients as it grows and takes up carbon dioxide through photosynthesis. When appropriately managed, seaweed cultivation can therefore contribute to nutrient recycling and carbon removal while generating income for coastal communities. Its ecological benefits, however, depend on the farming system, local environmental conditions and how the harvested biomass is used.
For women in fishing communities, the potential extends beyond an additional source of income. Seaweed cultivation builds on existing coastal knowledge and offers a livelihood that can be pursued without leaving the communities and waters on which their lives depend.
Since 2014, the Indian Council of Agricultural Research's Central Marine Fisheries Research Institute ICAR-CMFRI, has been field testing an integrated approach to seaweed cultivation in Tamil Nadu, Gujarat and Andhra Pradesh. Known as Integrated Multi Trophic Aquaculture (IMTA), the system combines different aquatic species so that the waste generated by one can serve as a resource for another.
In this model, high-value fish such as cobia are raised in floating sea cages. Mussels and oysters filter organic matter from the surrounding water, while seaweed rafts positioned around the system absorb dissolved nutrients. Each component performs a different function, allowing some of the waste generated during fish farming to support additional biological production.
The approach is designed to reduce the nutrient load released into surrounding waters by converting part of the waste stream into biomass that can be harvested or used for other purposes. Rather than treating fish, shellfish and seaweed as separate crops, IMTA brings them together in a system intended to improve resource use and reduce environmental pressures associated with aquaculture.
ICAR CMFRI Director A. Gopalakrishnan has highlighted the potential of the technology, saying, “This technology will help popularise and boost seaweed farming across the coastal states.”
Research published in Nature in January 2026 found that seaweed farms could remove an estimated average of 0.85 tonnes of carbon dioxide per hectare annually through enhanced alkalinity production alone. This estimate relates to a specific carbon removal pathway and should not be interpreted as the total carbon benefit of every seaweed farm.
The findings are relevant to integrated fish farming, where expanding cage aquaculture can increase organic and inorganic nutrient loads in surrounding waters. CMFRI's IMTA trials use seaweed to absorb some of these nutrient wastes, converting a potential pollution load into additional biomass.
Seaweed cultivation can therefore serve several purposes within an appropriately designed farming system: producing a commercially valuable crop, recycling nutrients and contributing to carbon removal. The scale of these benefits depends on local conditions and how farms are managed.
According to ICAR CMFRI's own estimates, India has 342 suitable seaweed farming sites along its coast, with a combined production potential of 9.7 million tonnes annually. Current production, however, stands at around 34,000 tonnes.
The gap between potential and actual production points to challenges beyond scientific knowledge or the identification of suitable sites. Expanding the sector requires an institutional framework that connects producers with reliable buyers, accessible market information, finance and appropriate regulatory support.
While community based seaweed farming has struggled to expand, commercial development along India's coastline has advanced through ports, industrial projects and other infrastructure. The question is how coastal governance can accommodate such investments while protecting ecosystems and the livelihoods of traditional fishing communities.
A 2022 audit by the Comptroller and Auditor General of India (CAG) found that Tamil Nadu's Coastal Zone Management Authority had incorrectly granted coastal regulation zone clearances to 114 of 175 commercial projects, or 65%, without forwarding them to the appropriate authorities for approval.
The coastal regulation zone framework was established to regulate development along India's coast and protect ecologically sensitive areas and coastal communities. Since its introduction in 1991, the framework has undergone repeated amendments that have changed the scope of permitted development. Frontline has documented how these changes have influenced the balance between coastal protection and commercial activity.
The effects of coastal development are also evident in the displacement of fishing communities. In September 2024, nearly 700 fishing homes in Kandla, Gujarat, were demolished as part of port expansion, displacing around 6,000 fisherfolk, according to reports by the International Collective in Support of Fishworkers ICSF and Land Conflict Watch.
The CAG audit also identified gaps in community participation in coastal governance. District-level committees in Tamil Nadu lacked representation from local traditional communities, while Andhra Pradesh had not established the committees at all.
These gaps matter for seaweed farmers because their livelihoods depend on access to coastal waters, secure cultivation areas and a say in decisions affecting the ecosystems they use. Coastal development and marine conservation policies that overlook local communities can undermine the conditions required for community-based aquaculture to succeed.
The allocation of public resources offers another way to examine the priorities shaping India's blue economy.
The Union Budget for 2026 to 2027 announced a record of highest-ever fisheries allocation of Rs 2,761.80 crore, supporting the sector's value chains, exports and coastal livelihoods. This represents an important investment in fisheries.
At the same time, Sagarmala, India's port-led development programme, targets Rs 12 lakh crore in investment over a decade. Both initiatives contribute to what is broadly described as the blue economy, which encompasses economic activities linked to marine and coastal resources.
Their different scales and institutional arrangements raise questions about how support is distributed among port infrastructure, industrial development and community-based livelihoods. Port projects benefit from established planning and regulatory processes, while small-scale producers often face difficulties accessing finance, stable markets and institutional support.
Data from ICAR CMFRI's 2022 publication illustrate the changes in India's marine fisheries sector. Mechanised, motorised and traditional fishing account for 82%, 17% and 1% of total marine landings, respectively. In 1960, the traditional sector accounted for 88% of India's catch. Despite this shift in the composition of landings, traditional fishing continues to provide livelihoods for a large share of the country's marine fishing communities.
These figures highlight the changing structure of marine production and the importance of ensuring that economic development also addresses the needs of small-scale fishers. For women seeking to diversify their livelihoods through seaweed cultivation, the availability of suitable coastal space, reliable buyers and institutional assistance can determine whether the opportunity is viable.
Differences in coastal regulation create further challenges for community-based marine livelihoods. Each coastal state operates under its own version of the Marine Fishing Regulation Act, with variations in rules governing seasonal fishing bans, net mesh sizes and permitted species.
Research by the Observer Research Foundation (ORF) identifies this fragmented regulatory landscape as a challenge to sustainable marine fisheries governance. Differences between state frameworks make it difficult to replicate successful community-based models across coastal regions without adapting them to each state's legal requirements.
Seaweed farming and integrated aquaculture also require coordination among fisheries departments, coastal authorities, research institutions, financial agencies and local communities. Where responsibilities are divided across institutions without clear coordination, farmers can face uncertainty over permissions, access to suitable sites and the support available to them.
A more consistent regulatory approach could help states share successful practices while retaining the flexibility to address local ecological conditions. For women-led seaweed enterprises, this would provide a clearer institutional pathway from small-scale cultivation to stable production and marketing.
The experience of seaweed farmers in the Palk Bay demonstrates why technical feasibility alone cannot sustain a livelihood.
Between 2000 and 2013, PepsiCo contracted directly with coastal self-help groups in the region, providing a relatively stable market for their seaweed. The arrangement helped make cultivation economically viable for participating communities. When the company withdrew, the sector experienced a decline.
A peer-reviewed study tracking Indian mariculture documents this cycle of expansion and contraction. It concludes that community-scale mariculture can remain economically fragile without a dependable source of demand, even when the farming system is ecologically viable.
The experience highlights a central weakness in the sector's development: producers can learn how to cultivate seaweed and have access to suitable waters, yet still struggle when buyers withdraw or prices become uncertain. A dependable market is essential for farmers to invest time and resources in production.
The consequences extend beyond seaweed cultivation. Lakshmi Kovvada, president of the Andhra Pradesh Traditional Fishworkers Union, has described the pressures facing women in fishing communities. In an interview with Mongabay India, she said, “Fisherwomen are being pushed out of the sector and into domestic work just to survive. Being a fisherman is challenging, and the fate of fisherwomen is even worse."
Seaweed cultivation offers one way to diversify livelihoods without requiring women to abandon their coastal communities. It builds on the knowledge and skills they already possess. Women constitute the majority of wild seaweed collectors along the Palk Bay, giving them experience that can support the development of cultivated seaweed enterprises.
Government support recognises the role women can play in this sector. Under the Pradhan Mantri Matsya Sampada Yojana, PMMSY scheme, women are eligible for an investment subsidy of 60%, compared with 40% for men. However, subsidies alone cannot guarantee viable enterprises. Without dependable buyers, clear information about prices and accessible routes to market, financial assistance may not translate into sustained income.
Indonesia provides a comparison. It cultivates the same seaweed species through women-led cooperative structures and, by 2021, had developed a billion-dollar seaweed industry and ranked sixth globally in carrageenan exports, according to the United Nations Industrial Development Organization. Its experience highlights the importance of building processing capacity and institutional support around community producers.
India's challenge is not simply to increase the volume of seaweed grown. It is to establish the market connections and support systems that allow producers to retain greater value from their work.
NITI Aayog's 2025 blue economy roadmap envisages fisher cooperatives and community participation through 2033. Its first phase runs until 2028, providing a near-term opportunity to establish the systems needed to support community-based mariculture.
Three measures could help translate these commitments into practical outcomes.
A dedicated procurement mechanism for seaweed produced by cooperatives could give farmers greater certainty about demand and prices. Sovereign blue bonds, with funds earmarked for mariculture cooperatives, could also be explored as a means of financing community-based aquaculture infrastructure.
Such a mechanism would reduce the dependence on a single corporate buyer, as experienced during the PepsiCo arrangement. A state-supported procurement or off-take guarantee could provide self-help groups with a more reliable route to market while making it easier for banks to assess lending to community-scale sea cage and seaweed farming operations.
The mechanism would need transparent pricing, clear quality standards and safeguards to ensure that the benefits reach producers. Public support should also encourage a diverse network of buyers and processors rather than replace one form of market dependence with another.
A model Marine Fishing Regulation Act could provide coastal states with a common baseline for managing marine fisheries and supporting community-based aquaculture. States could adapt its provisions to their local ecological conditions while retaining greater consistency in core regulatory principles.
ORF's research on marine fisheries governance identifies the difficulties created by the current state-by-state approach. A model framework could reduce the need to develop separate regulatory solutions for every state and make it easier to share effective community-based practices across India's coastline.
The process should involve traditional fishing communities, women farmers, researchers and relevant government departments. Their participation would help ensure that the framework addresses livelihood needs as well as resource management and conservation.
Women farmers need to know the prevailing market price of seaweed and identify potential buyers before selling their harvest. Suganthi's experience in Rameswaram, where learning more about the market enabled her to increase her income by 50%, illustrates the difference such information can make.
A digital procurement and market information platform linked to PMMSY beneficiaries could display current prices, buyer details, quality requirements and procurement opportunities. It could build on India's existing digital infrastructure for agriculture while incorporating the specific needs of coastal mariculture.
For the system to be useful, information would need to be timely, locally relevant and accessible to women with different levels of digital literacy. Local cooperatives and self help groups could help farmers use the platform, compare offers and negotiate with buyers.
The aim would be to reduce information asymmetry, strengthen the bargaining position of producers and make market access less dependent on intermediaries.
India has the scientific research, suitable coastal sites and experienced communities needed to expand seaweed cultivation. Integrated farming systems have demonstrated how seaweed can contribute to nutrient recycling, while existing cultivation practices offer women in fishing communities an opportunity to diversify their incomes.
The remaining challenges concern how these opportunities are supported and sustained. Inconsistent regulation, limited market information, unreliable demand and inadequate institutional coordination can prevent farmers from benefiting from the potential of the sector.
A blue economy that includes community-based seaweed farming requires more than production targets and subsidies. It needs dependable markets, transparent pricing, accessible finance and meaningful participation by the people whose livelihoods depend on coastal waters.
Before dawn in the Palk Strait, women are already cultivating seaweed and drawing on generations of knowledge about the coast. Whether this work can develop into a stable and environmentally responsible industry will depend on the support that reaches them, the markets they can access and the role they are given in decisions about their coastal future.