Fishing need not be a lottery. It can be a scientific endeavour, with researchers mapping the movements of different fish species, identifying the feeding hot spots, and providing precise locations for the fishermen to hunt, thereby saving them time, money, and fuel in the process.
Hyderabad-based Indian National Centre for Ocean Information Systems (INCOIS), under the Ministry of Earth Sciences (MoES), has been successfully issuing daily advisories on Potential Fishing Zones (PFZs) for tuna and other marine species by studying sea surface temperatures and chlorophyll distribution. The advisories are provided in English, Hindi, and eight coastal regional languages to benefit an estimated nine lakh or more fishing communities.
Nutrient influx
INCOIS scientists have now discovered that ‘Malabar sea upwelling’, the process of nutrient-rich deep water rising to the surface, plays a crucial role in determining mackerel abundance along southwest coast of India.
The influx of nutrients to the sea surface supports plankton growth, which attracts small fish for feeding and breeding. These small fish, in turn, draw the mackerel to these feeding grounds. Additionally, rainfall patterns and seawater temperature variations at different depths were found to influence the mackerel catches along the Malabar coast.
Scientists say the findings of the study conducted to better understand the relationship between ocean conditions and mackerel availability have significant implications for sustainable fishery management in Karnataka and Kerala.
“Our research provides valuable insights for predicting mackerel fish aggregation areas by identifying seawater temperatures at different depths and other key factors that aid in optimising fishing operations. This knowledge can help fishermen target areas with higher mackerel concentrations, reducing fuel consumption and improving their catch rates”T.M. Balakrishnan Nair INCOIS Group Director, Ocean Modelling Assimilation and Research Services Group
“Our research provides valuable insights for predicting mackerel fish aggregation areas by identifying seawater temperatures at different depths and other key factors that aid in optimising fishing operations. This knowledge can help fishermen target areas with higher mackerel concentrations, reducing fuel consumption and improving their catch rates,” says INCOIS Group Director, Ocean Modelling Assimilation and Research Services Group, T.M. Balakrishnan Nair.
AI predictive models
He pointed out that Artificial Intelligence (AI) and Machine Learning (ML) are at the core of developing a predictive model for Indian mackerel PFZ advisories, enabling more accurate and timely recommendations for fishermen.
These findings can also provide vital information to policymakers in developing sustainable fishery management strategies to ensure the long-term health of the mackerel population and the sustainable livelihoods of those who are dependent on it. Efforts are being made to transform the PFZ advisories into forecast services.
India contributes 90% of the world’s mackerel production. While 77% of the country’s mackerel production comes from its west coast, 23% comes from the east coast. The study also explores the relationship between the area’s PFZ lines and the mackerel landings along the nearby coasts.
Other scientists involved in the research—A multidecadal study of the Malabar upwelling system influencing Indian Mackerel landings along the coasts of Karnataka and Kerala, South-east Arabian Sea—are S. Jha, S.D. Sudhakar, S. Majumder and S. Joseph. The study has been published in the latest issue of Journal of Marine Systems.