Flagging shifts in species biology, distribution and environmental changes, marine scientists have warned that climate change is significantly transforming marine ecosystems and fisheries in India.

They highlighted the need for proper action plan for climate mitigation and ecosystem restoration at a two-day national seminar on Mitigating Climate Change Impact on Marine Ecosystems jointly organised by ICAR-Central Marine Fisheries Research Institute (CMFRI) and Institute of Social Sciences, New Delhi, sponsored by the Indian Council of Social Science Research, New Delhi.

“A key concern is the change in fish phenology—or life cycle patterns—where commercially important species are maturing at smaller sizes. Silver pomfret now matures at 280 g, down from 410 g. Similar reductions in size and fecundity are being seen in coastal prawns, sardines, and mackerels, affecting reproductive success and recruitment into fisheries” said CMFRI Director Dr Grinson George who delivered a keynote address.

On shifts in geography of fish stocks, he highlighted northward migration of species such as the Indian oil sardine, predicted under future climate scenarios driven by changes in food availability, rainfall, oceanic upwelling, and oxygen levels. According to him, fishermen lose a considerable number of fishing days each year owing to cyclone warnings and other extreme weather events.

Dr K R Sreenath, Director of Fishery Survey of India inaugurated the seminar. The effects of climate change are evident in coral reef bleaching in Lakshadweep, which poses a threat to biodiversity and coastal protection, said Dr Sreenath.

A community-oriented approach must be integral to policy-making to ensure local support and long-term success in conservation and adaptation efforts.

The US reciprocal tariffs on seafood trade are further placing Indian fishers in economically vulnerable positions, he added.

Dr Sreenath underscored the urgent need for accurate prediction models for weather events and fish species distribution and abundance, which are essential for sustainable fisheries planning and disaster risk reduction.

According to Dr K Mohammed Koya, Fisheries Development Commissioner, Govt of India, climate change has drastically altered the Lakshadweep ecosystem, significantly impacting fisheries. He noted that seagrass beds have been damaged and stressed the need for effective restoration. Introducing seaweed farming in the lagoons could be a solution, as it attracts rare species and benefits local fishing. The central government’s carbon market system could also incentivize fishermen and fish farmers to adopt these restorative practices.

Prof. Vinod Sharma, Climate Change Advisor to the Government of Sikkim, said coastal shorelines have been changing more rapidly since 2000 due to climate events. “The Arabian Sea has seen a recent increase in the frequency of cyclones. This has led to more saltwater intrusion in vulnerable coastal areas, which is seriously impacting the health of local communities”, he added.

Dr Surajit Mahalanobis, Senior Research Fellow at ISS presented overview of the seminar. Dr Shoba Joe Kizhakudan and Dr Pooja Sharma also spoke at the inauguration of the seminar.

A wide range of topics including adaptive management strategies, socio-economic resilience, nature-based solutions and innovation and emerging technologies are being discussed in the seminar that will conclude on Wednesday.