KOCHI: Has El Nino, the phenomenon that disrupts normal weather patterns, affected the marine ecosystem of Kerala’s coastal waters? The warming of the coastal sea, the decline in plankton production, the varying rainfall pattern, the change in upwelling - a process by which the cold water from the deep rises to the surface- are all sending disturbing signals.
The recent findings suggested that oil sardine, Kerala’s favourite fish variety, is migrating towards Tamil Nadu coast at times of unfavourable conditions along the Kerala coast, like EL-Nino. Amidst the gloom, there is some silver lining. The state has recorded a 170 per cent increase in the landing of sardines. While the annual landing of sardine stood at 48,000 tonnes in 2016-17, the figure went up to 1.25 lakh tonnes in 2017-18 recording a steep increase of around 77,000 tonnes.
The decrease in spawning efficiency and stunted growth have set alarm bells ringing for the fisheries sector. “The depletion of sardine stocks in Kerala’s coastal seas has adversely affected the livelihood of thousands of fishermen,” Matsya Thozhilali Aikya Vedi president Charles George told Express.“Sardine is the favourite fish variety for Keralities and the drop in catch has adversely affected the inboard fishing boats. Many fishing units have been shut down. While Kerala’s sardine catch fell to one tenth of the normal catch, the state started depending on fish coming fr0m neighbouring states.”
As there is not much demand for sardine in Tamil Nadu, the fish is being sent to Kerala. While the drop in catch left the Kerala fishermen jobless, the customers are not affected as sardines from Mangaluru and Tamil Nadu are flooding the market. Charles said around 60 truck loads of sardine reach the state from Mangaluru every day. “We have noticed a rise in the availability of oil sardine in Kerala coast after 2014. While the availability of sardines in Kerala waters plunged, harbours in Tamil Nadu coast got a good catch. There is a need to conduct a detailed study into the phenomenon. Even the taste of the oil sardine has changed,” he said .
“Biological changes such as growth retardation coupled with spawning failure in oil sardine along southwest coast of India in response to EL Nino phenomenon during 2014-’15 reduced their stock abundance resulting in poor catches said CMFRI principal scientist E M Abdussamad.