El Niño may trigger coral bleaching, hit fish catch: INCOIS

The Indian National Centre for Ocean Information Services (INCOIS), in a special bulletin, stated that the El Niño phenomenon — characterised by the warming of sea surface temperatures in the central and equatorial Pacific Ocean and known to influence the Indian monsoon — is continuing to develop and is expected to peak between November 2026 and January 2027.

As a result, sea surface temperatures in the Indian Ocean are likely to remain higher than normal until April-May 2027. The marine ecosystem in the northern Indian Ocean — including both the Arabian Sea and the Bay of Bengal — is expected to face thermal stress in the coming months, particularly during March-May 2027.

This could lead to increased coral bleaching, more frequent marine heatwaves, and a decline in fish catches, especially of sardine and mackerel. The reduction may occur due to the migration of fish stocks to more suitable habitats or a decrease in recruitment.

Additionally, fish may not attain desired sizes due to changes in marine environmental conditions associated with the developing El Niño. The sea state in the Bay of Bengal is expected to remain rough during the monsoon season, increasing the risk of coastal erosion and flooding along India’s east coast.

However, conditions in the Arabian Sea and along the west coast are likely to be calmer than usual, potentially extending operational windows for various marine sectors. Consequently, coastal erosion and inundation are expected to be less severe along the west coast during the ongoing monsoon season.

Senior scientist P.A. Francis said the institute has begun issuing specialised El Niño bulletins to highlight potential impacts on maritime sectors. The first such bulletin was released on Monday by Chevella BJP MP Konda Vishweshwar Reddy in the presence of scientists at the institute located in Pragatinagar.

INCOIS has advised maritime operators to closely monitor alerts, warnings and advisories issued periodically. The next specialised bulletin is scheduled to be released in the second week of July 2026, according to a press release by director T.M. Balakrishnan Nair.