Kochi: There are certain changes in marine ecology that fishermen can spot better than scientists. The transformation of the coastal food system is one.
Fishermen in Kerala have told scientists at the Kochi-based Central Marine Fisheries Research Institute (CMFRI) that an average of six species of fish have vanished from their usual catches. On the contrary, fishermen across Kerala also noticed that, on an average, only one new type of fish has been added to their catch in recent years.

This perception suggests that the climate-induced movement of fish species is not compensating for the losses in marine diversity.
The observational inputs of fishermen were collected as part of a first-of-its-kind study conducted by the CMFRI titled "Impacts, adaptation and mitigation efforts in Kerala’s coastal food system: a socio-ecosystem evaluation of fishing community responses to climate change".

Dr Reshma Gills, a scientist at CMFRI and lead researcher of the study, told Onmanorama that 905 fishermen who have been going to sea for decades were chosen for the study by random selection. Dr Gills emphasised that the study was based solely on the perceptions of the fishermen and was intended to understand their perspective on the phenomenon of climate change.

Dr Gills said that another study, which seeks to objectively validate the perceptions of the fishermen regarding loss of marine diversity, is underway at CMFRI. “We will be able to share specific information once that study is completed,” she added.

Fishermen also reported losing around 90 fishing days every year due to extreme weather events, taking a toll on their income. The study notes that while fishermen are aware of climate change, their perception of its direct effect on fishing days might not be accurate. While some may associate temporary unfavourable weather conditions with broader climate change, others may perceive seasonal variations or fishing bans imposed by the government as disruptions caused by climate change.

The study found that issues plaguing fishing communities vary across districts. While fishermen from Thiruvananthapuram reported reduced fish production and loss in marine population and diversity, respondents from Kollam expressed concerns such as changes in monsoon patterns and fishing seasons.

Alappuzha, which ranked second in inland fish production in 2024 as per Economic Review 2024, now grapples with declining fish production and shifts in fish breeding habitats.

While a decline in fish population was reported in most districts, difficulties in predicting wind directions and fishing times were considerably higher in Thiruvananthapuram and Alappuzha districts, adversely affecting the safety of fishing activities. Increased risks were also reported in Kozhikode and Kannur.

While intrusion of seawater into freshwater areas and increased operational costs posed challenges to fishermen in Malappuram, the study found that the fishing community in Ernakulam faced socio-economic challenges such as loss of workdays and dwindling income.

Even as the state frequently experiences extreme weather events, the CMFRI study found that 91% of the respondents had not received any training on dealing with climate change and natural hazards. The findings suggest a need for more awareness among fishing communities to deal with environmental risks.

According to the study, 42.6% of the respondents view information regarding climate change as “irrelevant” to them. “Blanket instructions result in loss of fishing days across the state. In such a scenario, many fishermen still trust their ancient knowledge and venture out to sea. This puts them at risk,” Dr Gills said. This indicates the need to provide region-specific information to fishing communities, she added.

However, Dr Gills noted that the state currently lacks the technology to provide precise information regarding specific regions.

The study has been published in the International Journal of Advances in Engineering Sciences and Applied Mathematics by Indian Institute of Technology, Madras (IIT-M).