Key Issues Affecting India’s Marine Aquatic Resources and Possible Solutions

India’s marine resources are among its most vital natural assets. With a coastline stretching over 8,118 kilometres, an Exclusive Economic Zone (EEZ) of 2.02 million square kilometres, and nearly 30 million people depending on fisheries for their livelihoods, the health of these ocean resources directly affects food security, rural employment, and coastal economies. Yet this wealth is under serious threat. Overfishing, weak governance, and accelerating climate change are straining India’s marine ecosystems in ways that, if left unchecked, could cause irreversible damage. Understanding these issues – and the policy tools available to address them – is essential for anyone studying sustainable natural resource management.

Overfishing and overcapacity: a deepening crisis
Bycatch and juvenile harvesting
Climate change and its impact on marine resources
Ocean acidification: a silent threat
Shifting species distributions and disrupted food webs
Policy and management strategies: what exists and what needs to change
Current regulations
Where the gaps lie
Suggested improvements

Overfishing and overcapacity: a deepening crisis

India’s marine fishing sector has grown dramatically over the past seven decades, expanding from modest artisanal operations to a largely mechanised industry. Marine fish landings from India’s coast reached 3.53 million tonnes in 2023, a six-fold increase from mid-20th century levels. This growth, however, has come at an ecological cost. Production has stabilised at 3-4 million tonnes annually, a signal that maximum sustainable yield has effectively been reached – and in many areas, surpassed.

The core problem is overcapacity – too many fishing vessels chasing too few fish. In Kerala alone, expert committees have repeatedly recommended capping mechanised trawlers at 1,500 to 2,000 vessels. The actual number of trawlers in the state exceeds double that recommendation, and scientific advice continues to be sidelined by political pressure. This pattern repeats across the western coast.

Mechanised fishing methods – particularly bottom trawling and purse seining – cause damage that extends well beyond the target species. Trawl nets drag across the seabed, destroying spawning grounds and disrupting fish breeding cycles. Shrimp trawling along the southwest coast has led to overfishing of prawns and a measurable decline in catch per unit effort since the mid-1970s. When fishing effort keeps rising but production falls, it is a clear ecological warning.

Bycatch and juvenile harvesting

Bycatch – the unintended capture of non-target species – is another serious consequence of overcapacity. Multi-species trawling indiscriminately sweeps up juvenile fish before they reach reproductive maturity. Nets with mesh sizes smaller than 25 mm allow juvenile fish into the catch, leading to premature harvesting of species like sardine and mackerel that cannot replenish their populations fast enough. This creates a reinforcing cycle: smaller catches push fishers to work harder and wider, which depletes stocks further.

The economic consequences are already visible among small-scale fishing communities. Artisanal fishers, who traditionally operated in nearshore waters, have seen their catches dwindle as industrial fleets dominate inshore areas. Rising sea surface temperatures, overfishing near the shore, and reef destruction have forced India’s fishers farther out to sea, where they face greater physical danger, higher fuel costs, and the very real risk of straying into the territorial waters of neighbouring countries.

Climate change and its impact on marine resources

Even if overfishing were brought under control tomorrow, climate change would still pose an independent and growing threat to India’s marine aquatic resources. The Indian Ocean is warming faster than any other tropical ocean. Sea surface temperatures in the tropical Indian Ocean rose by an average of 1°C between 1952 and 2015, and the ocean has been responsible for one-fourth of total ocean heat increase globally over the last two decades. This warming reshapes fish migration patterns, disrupts breeding cycles, and alters the entire food web.

Ocean acidification: a silent threat

Alongside warming, ocean acidification is quietly undermining marine life. As atmospheric CO₂ rises, the ocean absorbs roughly 30% of it, triggering a chemical reaction that lowers seawater pH. Since the Industrial Revolution, ocean pH has dropped by 0.1 units – a 26% increase in acidity when measured by hydrogen ion concentration. This may appear to be a small change, but its biological effects are significant.

For shellfish, molluscs, and crustaceans, acidification makes building and maintaining shells increasingly difficult – often described as the “osteoporosis of the sea.” India’s four major coral reef systems – in the Gulf of Kachchh, Gulf of Mannar, Lakshadweep, and the Andaman and Nicobar Islands – already face temperature-driven bleaching, and acidification further slows coral growth and weakens reef structures. Coral reefs serve as nurseries for a wide range of fish species, so their degradation has downstream consequences for fisheries productivity.

The socioeconomic risk is particularly acute in India. About 67.3% of India’s fishing households live at or below the poverty line, giving coastal communities very limited capacity to adapt to declining catches. A drop in shellfish or reef fish populations could directly affect both nutrition and income for millions of people. Despite the scale of this risk, India currently has no coordinated national ocean acidification monitoring network, and research on its effects on Indian marine species remains scattered.

Shifting species distributions and disrupted food webs

Warming oceans are also causing shifts in species distribution. As waters heat up, fish move toward deeper or cooler areas, changing where they can be caught and making traditional fishing grounds less productive. India’s total marine fish catch dropped approximately 2% in 2024 to around 3.47 million tonnes, partly attributed to climate-related disruptions including cyclones and rising sea surface temperatures. Species composition is also shifting – catches of Indian mackerel and threadfin breams are declining while certain sardine and anchovy populations temporarily rise, reflecting a restructuring of the marine food web rather than genuine recovery.

Phytoplankton – the microscopic organisms at the base of the marine food chain – are particularly vulnerable to warming and acidification. Disruptions at this foundational level can cascade upward, affecting every link in the food chain from small pelagic fish to the large predators, and ultimately to the fishers who depend on them.

Policy and management strategies: what exists and what needs to change

India has put in place several regulatory frameworks to manage marine fisheries, and these represent meaningful steps forward. However, experts consistently point to gaps in enforcement, inconsistent state-level regulations, and a disconnect between scientific advice and actual policymaking.

Current regulations

The National Policy on Marine Fisheries (NPMF, 2017) is the overarching framework guiding marine fisheries management in India, with sustainability as its stated core principle. Under its provisions and related acts, the government has introduced several targeted measures. A 61-day uniform fishing ban during the monsoon season within the EEZ gives fish stocks time to replenish during breeding periods. Destructive practices like pair trawling, bull trawling, and the use of artificial LED lights to attract fish have been banned. Sea ranching, artificial reef installation, and mariculture – including seaweed cultivation – are being promoted as sustainable alternatives.

Mesh size regulation is another important tool. The minimum mesh size for trawl nets determines which fish are caught and which escape, directly influencing whether juvenile fish survive to reproduce. Scientific recommendations call for a minimum mesh size of at least 35 mm, yet regulations vary widely across states – Gujarat mandates 40 mm, Kerala 35 mm, and Goa just 24 mm. This patchwork creates loopholes: juveniles protected in one state can legally be caught in the next.

Fishing area demarcation – dividing the EEZ into zones based on ecological sensitivity and fish stock health – helps reduce pressure on overexploited nearshore areas and directs vessels toward less-depleted offshore stocks. Zonation within India’s EEZ has been proposed as part of a national fisheries reform to manage fishing pressure more effectively.

Where the gaps lie

Despite these frameworks, enforcement remains the weakest link. A 2023 study published in Marine Policy found a weak and inconsistent relationship between fisheries policy and fisheries science along India’s west coast. Policymaking is frequently driven by political considerations – such as the timing of fishing holidays – rather than biological data. Monitoring mechanisms are limited, and compliance with minimum catch size regulations is observed only in certain states.

The fragmented governance structure is a systemic issue. Each coastal state administers its own Marine Fisheries Regulation Act within the 12-nautical-mile territorial limit, while the central government manages the EEZ beyond that. This split creates inconsistencies that are exploited by large-scale operators. Illegal, unreported, and unregulated (IUU) fishing further undermines data integrity, making stock assessments less reliable and complicating management decisions.

At the international level, the Indian Ocean faces similar governance gaps. A WWF report found that squid fishing in one unregulated area of the Indian Ocean grew by 830% in just five years, with no oversight or monitoring. Since the Indian Ocean supplies 20% of global tuna demand, allowing such gaps to persist has consequences that ripple far beyond India’s borders.

Suggested improvements

Bridging the gap between policy and science requires structural change at multiple levels. Several improvements are widely recommended by researchers and conservation bodies:

Harmonised national standards for mesh sizes, closed seasons, and catch limits would eliminate the regulatory patchwork that currently enables overfishing to shift between states. A national framework – rather than 13 separate state-level acts – would be more enforceable and scientifically coherent.

Science-based catch quotas tied to regular stock assessments would ensure that fishing effort stays within biological limits. India’s marine fish production has plateaued, making it essential that harvest levels are calibrated to what ecosystems can sustain rather than what markets demand.

Community-based fisheries management, which involves local fishers in monitoring and decision-making, has shown promise in other contexts and aligns with India’s large small-scale fishing sector. Empowering artisanal communities as stakeholders – rather than treating them purely as beneficiaries of top-down policy – can improve both compliance and ecological outcomes.

Dedicated ocean acidification monitoring is another urgent need. Integrating OA data into fisheries management would allow policymakers to anticipate which species and regions are most at risk and design targeted interventions before populations collapse. Aligning this with SDG 14.3, which specifically addresses ocean acidification, would also support India’s international sustainability commitments.

Finally, ecosystem-based fisheries management (EBFM) – which considers the health of entire marine ecosystems rather than targeting individual species – is increasingly recognised as the most robust approach for long-term sustainability. It accounts for the interactions between species, habitats, and human activities, and is far more resilient to the complex stresses of climate change than single-species management alone.

What do you think? Given that India’s marine fish production has effectively plateaued at its maximum sustainable yield, should the government prioritise reducing the number of mechanised fishing vessels even if it means short-term economic hardship for fishing communities? And with ocean acidification research in India still limited and fragmented, what should be the first concrete step – better monitoring, stronger policy integration, or increased public awareness?

References

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Table of Contents

Overfishing and overcapacity: a deepening crisis 🔗

Bycatch and juvenile harvesting 🔗

Climate change and its impact on marine resources 🔗

Ocean acidification: a silent threat 🔗

Shifting species distributions and disrupted food webs 🔗

Policy and management strategies: what exists and what needs to change 🔗

Current regulations 🔗

Where the gaps lie 🔗

Suggested improvements 🔗